Deep
by CharlieNozaki
Summary: As a marine biologist with the Bio-Aquatic Rescue and Testing Institute of East Blue (B.A.R.A.T.I.E.), Sanji has encountered his fair share of underwater life. But none quite like the ball of algae that flops on-deck one fateful day… [Modern AU. Merpeople. ZoSan].
1. Catch of the Day

"Sanji! The last one's comin' back around!"

"Would you shut up, Patty? I can see that."

The blond grumbled under his breath, but pushed his annoying colleague out of his mind, instead focusing the barrel of his gun straight at the ridged dorsal fin currently cutting through the water straight towards the side of the boat.

The research vessel bobbed lightly with the waves, making it difficult to keep his aim on the creature, but one blue eye closed and he concentrated, tilting the gun downwards, slowly….patiently.

The fin came closer….closer.

And when it had nearly reached the platform on which he knelt, Sanji pulled the trigger, sending the archival tag shooting out and clamping onto that large fin.

The fish thrashed violently, splashing a spray of ocean water into Sanji's face before it dove down quickly into the depths to escape any more flying projectiles, as harmless as they were.

The blond merely laughed, shaking out his hair and pulling up his shirt to wipe at his face. At least his sunglasses had protected his eyes, but he didn't care.

That marked the last of the school of elusive swordfish they'd been tracking all damn day, trying to get new tags on them now that some of the juveniles were starting to mature, a difficult task given their nocturnal nature.

But, a bit of mackerel and herring scattered into their territory as bait, and they'd lured out quite a few that hadn't been tagged.

The blond stood, balancing effortlessly on the swaying platform that jutted out from the boat's stern, despite the lack of railings. Days spent out at sea with his team had gifted him with rather sturdy sealegs.

A glance to the deck afforded him a view of Patty complaining to Carne rather loudly, something about Sanji being barely twenty-four years old, the youngest on the team by decades, and thus, having no right to boss people around like he always did.

Carne wholeheartedly agreed as the two moved around to the bow of the small schooner to secure a few tanks of fish they were taking back to the lab.

Sanji just smirked, stealing one last look behind him at the open ocean, nothing but blue skies and sunshine that was beautiful enough to keep his mood up even with those two bitching.

Maybe he had been fucking lucky, stumbling into this position as he had, while he knew Patty and Carne had worked their asses off for years through school and college just to land their first jobs at small-time aquariums.

But honestly, the sea had been a part of Sanji's life for - well, since before he could remember.

His birth parents had fucking dumped him on a beach when he was a baby. The ocean had practically been his _mother_ , for fuck's sake.

And then to be adopted by a shitty geezer? But a shitty geezer who just so happened to be a renowned marine biologist? One who'd written countless research articles, given dozens of university talks, and even filmed a few documentaries in his day?

Yeah, it might not have been in his blood, this work, not technically at least, but it was definitely ingrained in his soul.

He loved it though, rescuing animals, working with them, being out on the ocean and feeling the warm breeze lifting his hair.

It was freeing, and although he wasn't naturally inclined towards science, he was stubborn and persistent, and that was what had gotten him here in the end. Because if he hadn't been, it wouldn't have mattered _who_ his father was. He wouldn't be out on this boat with a fucking dart gun in his hand, tagging badass swordfish like the pro he was.

"Hey, brat. Get up on deck. We gotta move out."

A gruff voice sounded from the door of the small cabin, an older man - also blond, along with a weathered face, and a rather impressively long mustache that stood out on end - poking his head out.

"What?" Sanji asked, though he did step up off the platform onto the main deck, hooking the metal chain across the opening behind him, just as a precaution. "But what about the reef samples?"

"It'll have to wait," Zeff replied, shooting his son a look that said this was non-negotiable. "Just got a call from a private fishing vessel, due east. Somethin' big got in a fight with their propeller. Captain said he thinks it's a great white."

Sanji frowned, crouching down to the floor to start dismantling and repacking the tagging gun into its case. He shot eyes to the metal hatch in the floor that led down to the big species holding tank nestled below deck.

"There's no way a great white's gonna fit in there if we need to take it back," he muttered, hoping the assumption was wrong and it was something smaller.

"That's provided it's still alive," Zeff replied grimly before heading back into the cabin to start up the engines.

Sanji just huffed out a breath, grabbing the railing when the geezer floored the boat forward across the water and turned it hard to the east. He couldn't even take much amusement in the way Patty and Carne stumbled about on the other end of the boat, unprepared for the sudden burst of speed.

Great whites were a vulnerable species. Hell, most sharks were to some degree, and to potentially lose even one was something they should always try and avoid.

They were the Bio-Aquatic _Rescue_ and Testing Institute of East Blue. Not the Bio-Aquatic _Assume the Damn Worst Association_.

* * *

Maybe his dad was being realistic, but Sanji chose to remain optimistic, letting that familiar feeling of flying over the waves comfort him.

By the time they pulled their boat up beside the small fishing vessel that had apparently called them - the _Mihawk_ , if the name scrawled along the side of its weather-beaten maroon exterior was anything to go by - Sanji was already leaning out over the rail, scanning the waters for any sign of their potential victim.

Patty, Carne, and Sanji's father were already preoccupied with discussing the details with the boat's operator, a tall, intimidating man with black hair, a sharp goatee, and a mustache that looked far too dignified for any fisherman Sanji had seen.

But none of that mattered. What did was the amount of blood saturating the water around the boat, even splattered along the bottom lip of the hull where the lapping waves couldn't reach.

Shit.

It looked like a fucking _feeding_ ground, and Sanji began to worry that maybe the old geezer was right after all. Maybe they _would_ have to document a casualty…

He heard his dad advise the fisherman to head out so they could do a sweep of the area, possibly with nets if necessary. And the fisherman obliged, nodding his thanks, piercing yellow eyes meeting Sanji's for a moment before he moved back to his helm, started up his boat's engine again and rode off, leaving their little crew alone at sea once more.

"Boss, maybe we should start with sonar. If it's big enough, the tags might register," Carne was saying, and Zeff agreed, the three men squeezing into the tight cabin together to start on that.

"Brat, set up the transport gurney. And keep an eye on the water," his dad called out to him, voice muffled through the cabin window, and Sanji had to roll his eyes.

"Right, because I can obviously do both at once," he muttered, ultimately deciding to get the gurney ready first, though he was all ears in case he heard anything thrashing about in the waves.

From the port side of the boat, below the railing, near the floor, he unclamped two long metal poles, between which were stretched a durable yet porous canvas material that made it much easier to lift and move large species.

Even if the distance from the stern's platform to the transport tank was relatively short, it helped to have a bit of leverage to lift a squirming fish.

He spread it out and slid the apparatus towards the step to the platform, standing and unhooking the chain he'd secured earlier, in case they needed to move fast.

A glance behind him across the deck to the cabin, where the three men still stood comically hunched over the sonar screen, studying closely.

The blond sighed, knowing it was sometimes just as efficient to search the water's surface with the naked eye, especially when dealing with injured fish that might not be able to swim well.

So he didn't join them, merely stepped out onto the platform again, grabbing a support pole that rose above the railing so he could lean out over the water more easily.

It was still a sickly red color, and while it might have looked worse than it was, Sanji still had a twisting feeling in his gut as eyes scanned the depths for anything, a glint of sun rays on scaly skin, a ripple in the water not caused by waves…..anything…..

Suddenly, a hollow bump directly below his feet that admittedly startled him, the blond jolting a bit before he immediately dropped to his knees, fearlessly gripping the edge of the platform and peering over it. His head was entirely upside down and the tips of his hair flopped into the water with every low dip of the boat in attempt to see underneath.

It was quiet though. The water was calm, and for a moment, he thought he'd imagined the sound.

Until, that is, he saw a glimpse of a large caudal fin, limply floating its way out from beneath the boat.

His heart leaped into his throat, eyes widening, and he risked reaching down and giving the water a splash, to see if it would cause a reaction in the creature.

But no, nothing. It merely continued to bob there lifelessly, a bit more of its tail becoming visible as it shifted beneath the boat, dangerously close to their own inactive propeller.

A sinking feeling filled his chest, because, while sharks could be slow-moving….they were never this limp, nor did they float so readily.

Fuck.

Sanji shot his head up to call out to the others, "Hey! Don't move us at all! I think I found something!"

But they either didn't hear him or chose to ignore him, so Sanji growled to himself and leaned over again, hoping he wouldn't get his arm dismembered by reaching down to try and grab the end of the shark's tail himself. He could grab a pole, but he worried about losing sight of it in the time it took to gather the tool.

So he slid fully down to his stomach on the platform, pushed himself out over the water as far as he could, and curled himself underneath, hand darting out to grab hold of the shark's fin.

No reaction from the animal, even with his strong, sudden grip, so he gave a hard yank backwards in order to get it out from under the boat.

He retracted his arm as soon as he did, watching as a spotted tail slid its way backwards out into the sunlight. The thing was huge, and a bit beat-up, scars marring its dark green skin, but nothing that looked fresh yet.

The secondary dorsal fin came into view, followed by the larger one most commonly seen in dumb shark movies.

And he thought he would see the head appear a second after he saw gills….

Until, with utter confusion, he noticed the skin shifting in tone somewhat, transitioning to a pale color that was almost-

Skin.

 _Human_ skin.

That tail, which _definitely_ belonged to a massive tiger shark, had suddenly morphed into human skin, a human _back_ , shoulders, a fucking green head of hair.

And just like that, floating facedown in the water before him was a creature that was fucking half shark, half _man_.

And no, he wasn't fucking imagining things. Not after blinking countless times, removing his sunglasses, and giving himself a hard slap in the face.

What.

The.

Fuck.

" _Hey! Get your asses back here!_ _ **Now!**_ _"_ Sanji screeched in panic, scrambling back away from the water, despite his readiness to nearly dive in a second ago.

This finally drew the attention of his crewmates, Patty first looking out through the cabin door….until he caught a glimpse of Sanji practically cowering on the floor of the platform.

He made his way over….

And repeated Sanji's same reaction.

In fact, it happened two more times after that when Carne and Zeff joined them.

"What _is_ that thing!" Patty yelped, recoiling with shock and near horror.

"It's - it's-" Carne stammered. "Did the shark _eat_ someone?!"

"Hell if I know!" Patty shot back. "It sure as hell looks like a mermaid to me!"

"Don't be stupid! Mermaids aren't real!"

"Then what the hell do you call that thing?!"

Patty and Carne continued their panicked argument, even as Zeff pushed past them to join Sanji on the platform, lowering his aching joints to crouch beside his son, a deep, confused furrow to his brow before he muttered, "Get it up here."

His calm decisiveness was enough to have Sanji glancing over at the man rather helplessly. This was - this was _insane_ , right? Was it _really_ happening? Was it some prank?

But when eyes flicked, a little fearfully, back to the creature, he noticed the blood swirling in the water, more red than before, and he knew he had to act first, think later.

The creature was still within arm's reach, so he took a deep breath, then leaned out to grab its large dorsal fin, using it as leverage to flip it over to its back, fully prepared to find some kind of fish-alien monster right out of science fiction staring back at him.

What he got was the exact opposite.

What he got was a very bloody male human torso, albeit connected to a shark's tail, but as human as they came.

The bleeding stemmed from a nasty diagonal gash that ran the entire length of that torso, from left shoulder to right hip, probably the result of that run-in with the _Mihawk's_ propeller.

Sanji had to shift his gaze away from the sickening wound, only to have it land on the man's face, a face that was also completely human.

Fuck, he was actually….perfectly handsome. Nothing ugly or monstrous at all.

But he was also completely still and pale, eyes closed and mouth slack, a bit of blood trickling down from the corner of blue-tinged lips.

And the fear that they were already too late suddenly seemed even _more_ dire and terrifying than before.

"Go on," Zeff urged him again, forcing Sanji to snap himself out of his thoughts and into the moment once more.

He moved, managing, with some difficulty, to get arms underneath the shark-man's, hoisting him up only a little.

" _Fuck. He's heavy-help me out here,"_ Sanji gritted out, and thankfully, Patty snapped out of his bewilderment to grab ahold of the guy's tail, lifting him as they would any large fish while Sanji backed himself up towards the main deck.

Thank fuck he'd laid out the gurney because it was straight on with minimal burden, though he had to be careful not to crush his dorsal fin when they laid him out.

And there, on their deck, they suddenly had a very real - _something_ \- that was _far_ too human for comfort and _far_ too close to death.

Sanji threw all scientific deduction out, even as the other three immediately began consulting with each other.

Because, at the very fucking least, they had a creature here that was _half_ human.

Nevermind if it was scientifically unheard of. That would fucking have to wait because this guy was bleeding out. And he wasn't breathing. Maybe he used his gills, not lungs, but out of the water, gills wouldn't work either, and shit, what if he used ram ventilation on top of that?

Dammit, there were _so_ many problems here, but there was one question that _definitely_ needed answering.

Was he even fucking alive?

And that was why Sanji found himself kneeling urgently beside the man, jamming fingers to his neck to feel for a pulse like he would with any human.

" _Come on…"_ he breathed quietly, impatiently, eyes on the man's still features the whole time. " _Come on, you freaky bastard…"_

Fingers pressed a little harder…

But then he felt it. The gentle thrum of life beneath his fingertips, and he immediately grinned with relief.

Fuck yes, he was still fighting.

"He's alive!" the blond announced, looking up at the others, who were caught in a debate about what the fuck to do.

"...They'll have to run a necropsy," Carne was saying. "And probably - wait, _what?!_ It's _alive?!"_

"Yes!" Sanji insisted. "And he's got fucking gills, so let's get him in the holding tank!"

He didn't hesitate, just hurried to his feet with a brush of fingers against the unconscious man's cheek, and worked to unlatch the hatch himself, throwing open the metal cover to reveal the highly-oxygenated churning water of the tank below.

The shark-man's body was long. He might not fit entirely, but as long as they could get his gills under, then that should be enough.

Thankfully, Patty decided to make his huge arms useful again, helping him to lift the poles of the gurney and shuffle him back until they could slide him into the narrow tank.

He didn't fit, as Sanji had assumed, his upper half still out of the water, which was an odd sight indeed, almost like they had someone using their holding tank as a jacuzzi.

But that wasn't the case, and Sanji instinctively held onto the guy's head to keep him from slipping under entirely.

"What do we do about his wound?" the blond huffed, fingers sliding gently through green hair, brushing some of it off his forehead automatically. "It's on his human half - that's not really our jurisdiction."

The squelch of boots across the wet deck, and Sanji craned his neck to see Zeff already heading back towards the cabin calmly.

"If he's really part shark, then he'll heal up fast on his own," the man said nonchalantly. "Let's see if he lasts at least back to the lab."

And then he moved inside to start up the boat again.

Sanji growled, even more irritated when Patty and Carne continued to look somewhat repelled by the whole situation, though they were both most likely still trying to work through what the hell was even happening.

"We're gonna have to report this to the M.A.R.I.N.E.S., huh," Carne mumbled, drawing an even more apprehensive look onto Patty's face and a feeling of dread in Sanji's chest.

"Don't see no way around it..." Patty muttered in reply, gaze fixed intently on the shark-man in the tank.

Sanji clenched his teeth as the whir of the boat's engine started up, hoping to fuck there _was_ a way around that…

* * *

The ride back to the lab wasn't long by their normal standards, but that day, two hours felt like an eternity.

Sanji sat there the entire time by the tank hatch, sitting behind the merman and crossing his legs so he could situate his unconscious form a bit more comfortably, leaning him back against his legs.

It was fucking hot out there on the white deck, even in the waning afternoon sun, and he could feel a sunburn coming on, in his cheeks and nose especially, but still Sanji sat there, tending to the merman as diligently as he would any other animal.

Not that this guy was an animal, but - well, fuck if he knew what he was capable of. Maybe he looked human from the waist up, but who was to say what kind of brain he had?

Still, in that moment, the only thing that mattered was keeping him alive, so there Sanji sat, absently splashing water up over his exposed half to keep him moist as the time passed.

Miraculously, the bleeding on his torso had actually slowed, still leaving a bright red line across his skin, but certainly not gushing blood. Maybe his dad had been right about his healing abilities…

He checked the guy's pulse periodically, and it even seemed to strengthen again, color coming back to his face and lips, most likely from the oxygenated water, and Sanji started to allow himself to relax, just a little bit, over time.

Or, as much as one _could_ relax and process the fact that they were currently transporting a fucking _merman_.

Of course, it didn't _really_ sink in until Sanji found himself standing in front of one of the shallower rehabilitation tanks back at the lab that evening, after sneaking in their cargo earlier through the currently-empty sea lion enclosure.

Zeff didn't want any of the four of them breathing a word about the merman's presence until they were certain of whether he was going to live or die, and there was a good reason for it.

The Maritime Animal Research Institution of North, East, and South Blue was well-known for putting research first, above all else, most particularly their research subjects' well-being.

B.A.R.A.T.I.E. operated underneath that larger institution, unfortunately falling under their jurisdiction, therefore forced to report to them of their findings, but their ethical values differed greatly.

Sanji knew Zeff had been trying to make their operative independent, much like O.H.A.R.A., the Ocean Habitat Aquatic Research Association over in West Blue, had done, but it was difficult.

And Sanji could sense his father's unhappiness with the situation as the two of them stood in front of the glass window of the tank, watching the merman hovering there in the water, still unresponsive, but certainly more peaceful-looking.

"I worry we can't keep this under wraps," the older man said, arms crossed over his chest as he observed their patient. "This is….something else. I never expected something like this to…."

He trailed off, brow furrowed and wrinkles prominent on his forehead.

Sanji frowned and sighed, watching the ethereal way the merman's necklace of black stones floated gently in the water, those three golden earrings on his left ear doing the same.

Surely jewelry had to be an indication of culture….and thus, _human_ qualities….right?

"So we make sure he's okay and let him go again. Pretend it never happened," Sanji said, then turned his head to glance over at Zeff. "Not sure how you're so calm about this though. This is absolutely batshit insane."

Surprisingly, Zeff flicked eyes to his, a strange….almost nostalgic look passing across his face for a split second.

But then it was gone, as quickly as it had come, leaving Sanji to wonder if he'd imagined it.

The geezer looked away again, back to the floating merman.

"The ocean's a big place," was all he said.

Then he let out a sigh of his own and turned away, reaching out to pat Sanji on the shoulder as he walked off.

"Don't stay here all night, eggplant. It'll get cold," he grumbled over his shoulder, crossing the huge tank-filled room, footsteps echoing, easily highlighting his slightly uneven gait that came from a limp.

And eventually, the doors at the other end, past the turtle tanks near the feeding room, slammed shut, leaving Sanji alone with nothing but the faint sloshing of water here and there, and the whirring of pumps that kept the water oxygenated.

Don't stay here all night.

Sanji gave a little scoff.

Why _wouldn't_ he when he had a fucking _merman_ in the shark tank?

He and Zeff shared a bungalow just off the lab lot, close enough that they could be reached easily in case of an emergency.

But at a time like this, with such a peculiar and possibly dying patient?

He'd much rather stay.

So he grabbed a swiveling chair from one of the lab benches that lined the walls, wheeling the thing across the damp floor and parking it backwards in front of the tank window.

He threw a leg over it, straddling the seat and resting his arms and chin on the backrest.

He'd _definitely_ stay here all night.

* * *

Sanji's fascination with merfolk went back as far as he could remember.

It had started with mermaids, and it wasn't a _fetish_ , dammit, but definitely a fascination.

They weren't even real, and yet he knew all the lore that circulated the waters around East Blue. He'd annoyed his dad with questions about them, _devoured_ any movie with them, had even considered getting a tattoo with one.

But the tattoo idea came after he'd met Ace, who already had a few. After things had changed rather significantly for him.

Ace was in the Navy, stationed at the base not too far from the lab.

Sanji had still been in college, but he'd accompanied his dad there to request permission to run testing in Navy-controlled waters.

Ace had given them a tour of one of the ridiculous armed destroyer ships.

His smile had been so vibrant and endearing, and Sanji had been only nineteen, just beginning to question why a man's smile would have such an effect _period,_ when, up until that point, it had only been girls….

Their romance had been short and secretive, difficult because of their schedules, but also incredible, not to mention eye-opening. And though they'd parted less than a year later, they remained good friends, and Sanji was forever grateful for the newfound confidence and understanding of himself.

That wasn't to say he had lustful eyes for everything male that crossed his path. He didn't even _really_ feel that way about women either, most of any showy flirting and doting borne out of the great respect he held for them.

But he no longer suppressed or denied it when his mind fixated on what, as far as he'd assumed for the first chunk of his young life, had been the wrong gender.

And he wasn't going to deny, as eyes fell on the merman's still features, that this guy might even top Ace in the looks department.

Well, fuck.

This was absurd. This was a potential scientific _breakthrough_ right here, and yet there he was admiring (and maybe envying a bit) how damn beautiful and chiseled this fucking _shark-man_ was.

He sat there studying for a while, decided to pull his small notebook out of his shorts pocket, and started making notes to distract himself, detailing the pattern of his tail, a deeper green than most tiger sharks. But that was definitely a tiger shark, the longer, more angular caudal and pelvic fins giving it away.

He noted how smoothly his shark skin transitioned into human skin, watched the gill slits where his hips should be that, thankfully, seemed to be pumping on their own despite the merman's rather stationary position. It was a damn _good_ thing he hadn't turned out to be a great white. Otherwise, he would've surely asphyxiated by now.

His inner physiology was, of course, still a mystery, one that, as far as Sanji was concerned, might be better left unsolved given the fact that they were dealing with something far more human than anything they were used to.

For now, Sanji kept an eye on his wound, the movement of his breathing….and maybe his strong jaw, his lips….but only a little, particularly as he grew more tired.

Soon after, he slipped his notebook back into his pocket, hooked his pen on his lanyard and found himself drifting, eventually seeing nothing but blue….

Bubbles and blue….

So much blue…

* * *

Sanji didn't know how much time had passed when he unexpectedly jerked awake from the sensation of nearly sliding right off the chair.

Dammit. He quickly righted himself, gripping the backrest and rubbing at his chin, which had a good, sore impression of the chair back from resting it there for too long.

He scrubbed at his eyes next, feeling disoriented as he checked his watch, entirely baffled by the fact that it was now close to three in the morning, and he was still in the rehabilitation room, in his khaki shorts and work polo.

What the hell had he been….

….doing….

Suddenly, eyes focused in on the magnificent tail currently pressed against the glass of the tank window before him, its lazy lateral swish as his gaze traveled upwards over a human torso, that slash from the propeller still red and sore-looking but no longer bleeding at all.

And then he locked eyes with a pair that were dark gray, and not entirely human, their owner resting arms casually on the lip of the tank and peering down at Sanji over the edge.

The blond could only blink for a long moment, as his mind fought to assert that he was indeed awake, drawing on memories from earlier that day.

And once he'd accepted that the merman was still very much real, the second wave of shock hit.

"Holy shit - you're _okay!"_ he yelped, straightening and nearly rolling away on the chair in his haste to stand and get himself closer to the merman's level.

No response, however, the man just tilting his head a little curiously, his dark eyes moving up and down Sanji's form briefly before settling on his face again.

His hair was nearly dry, Sanji realized. How long had he been fucking watching him…?

"I-" he stammered, suddenly having no clue what to do or say now that he was confronted with a _conscious mystery of science._

Fuck, he was part fish. Who was to say he even understood him?

"Okay, um - shit - uh-" A few paces left, then he rounded on the guy, who didn't seem spooked by the sudden movement in the slightest. "Do you understand what I'm saying? Is this - I mean - can you talk?"

Again, no response, and Sanji let out a frustrated noise, bringing a hand up to rake through his hair.

"Ugh. No, that's stupid," he mumbled to himself, now pacing to the right. "He's a fucking _fish!_ Why would he understand humans?"

Of course, during his bout of mutterings, he completely missed the slow quirk of the merman's brow, the almost smirk that tugged at his lips that was certainly far more sentient than any mere _fish_...

"Okay!" Sanji suddenly huffed out, turning back to the merman with a determined look on his face.

He then lifted a hand to silently slash over his own torso in imitation of the merman's injury. As soon as he did that, he doubled over, dramatically miming pain for a second before straightening again and holding up hands in question.

All he received in reply was a few blinks, and then a confused furrowing of the man's brow.

Sanji let out a breath, held up a finger to indicate he was going to repeat the gesture, doing so with far more emphasis, even a pained noise, then pointing at the merman's chest insistently, fucking _hoping_ he got the message.

This time, the merman's expression changed to one that Sanji definitely recognized as an absolute 'What the fuck' that was so human and so _mocking_ that the blond actually rolled his eyes.

If that was the face he pulled, there was _no way_ the merman hadn't understood his gesturing at least, and Sanji was _not_ going to look like an idiot by repeating himself over and over to that condescending look.

He growled, resisting the sudden urge to flip the guy off for some reason, then decided he'd try something else.

He turned on his heel and stomped over to the set of metal stairs that climbed up the side of the tank, leading to the small feeding platform that jutted out over the water.

The merman watched him, but didn't move from his position right away, even as Sanji crouched down closer to the water's surface.

"Come here," he said, lowering his voice a bit and gesturing for the guy to come to the platform.

When that yielded no reaction though, he gestured more insistently, saying, "Come on. It's okay, I won't hurt you, just - come over here. Come on...come on."

It got to the point where he was essentially calling a dog over, and it seemed to annoy the merman enough - his eyes narrowing and lips pulling into an irritated line - that he actually did approach slowly….only to indignantly splash the blond in the face.

Sanji spluttered, infuriated when all he saw on the stupid shark-man's face was a smug little smirk.

 _Fuck_ him, what the hell! First encounter with a merperson and he was turning out to be a complete, clueless dick!  
"You are _seriously_ ruining my fantasies here, you know that, ya damn fish bastard?" he grumbled, wiping salt water out of his eyes and glaring down at the man. "And here I thought you were gonna _die!_ Not wake up and be a shitty _annoyance."_

The merman just kept up that maddening grin, revealing slightly-pointed teeth, watching Sanji with interest for a second.

Then he swam a little closer, looked Sanji straight in the eye and said, in a perfectly normal-sounding voice, "Food."

Sanji's jaw dropped open, the blond having to brace himself on the fucking edge of the platform so he didn't tumble into the water in his shock.

"Wha-" he stammered eloquently, eyes wide. " _What?"_

The merman rolled his eyes in response, fixed Sanji with a look, then slowly mimed bringing something to his mouth, and chomping into it with fervor, turning Sanji's stupid charades game right back on him.

He gave Sanji a pointed look again and repeated, "Food."

An unintelligible choking noise left the blond of its own accord before he shook his head quickly.

"You can _talk?!"_ he screeched, voice echoing around the vast room. "Are you fucking serious?! You're sitting there making me look like an idiot, and all along you could fucking-!"

But suddenly, the merman shot out of the water, one of his hands clamping down hard on Sanji's jaw, dragging his face down towards the water forcefully with a growl.

"Not - _everything_ \- understand," he gritted out with some hesitation, and a hint of an odd accent. "Stop - _talking."_

Then he released the blond with a shove of his hand, Sanji's sunglasses nearly sliding off his head into the water before he hastily hooked them on his shirt collar instead.

"Ugh, fuck you!" Sanji hissed, trying to steady his breathing and act like he _hadn't_ nearly been assaulted or drowned by a freaking brute of a _merman_.

So the guy understood and could speak at least _some_ human language. He should be fascinated, but really he was just aggravated now.

Sanji huffed out a breath and sat up, glaring down at the shark-man before he finally asked, "Well, what do you eat? I know tiger sharks will pretty much go for anything, so depending on how hungry you are, I can-"

The merman dropped his head back with a loud, frustrated groan, enough to shut Sanji up again, realizing that he probably _was_ at fault for speaking too much now, so he pinched the bridge of his nose to calm himself.

"Shit," he cursed, then lifted his head again with conviction to slowly ask, "What...food?" as if speaking to a goddamn baby.

The merman scowled at the tone, seemed to pause to think for a second before a smirk began to return to his lips, a devilish glint in his eye.

" _You?"_ he replied pointedly with a flash of teeth, and when Sanji automatically paled, the bastard snickered and looked far too pleased with himself.

" _No!"_ Sanji asserted, backing away from the water's edge some before getting to his feet and retreating to the stairs so he could make his way to the feeding room. "You'll eat what I give you, how's that!"

And the guy absolutely did, as Sanji watched, ten minutes later, the grotesque display before him - the merman literally tearing into a huge-ass raw tuna with sharp teeth, just as, well, a _shark_ would, chunks of meat floating to the surface now and again as he ate rather sloppily.

Thankfully, he did it underwater, so Sanji waited, crossing legs under him and resting his chin on a palm, eyelids beginning to droop slightly, but determined to stay awake now.

It didn't take long before the ripples and sloshing of the water, brought about by the merman's animalistic feasting, began to calm, and a few minutes later, a wet algae-head popped back up over the water and dumped a perfectly clean and intact fish skeleton on the platform beside Sanji.

Sanji quirked a brow at it for a second, then turned that look back to the merman, trying his best to look unimpressed despite being quite the opposite.

The merman floated back in the water lazily, crossing arms over his chest and watching Sanji again with an intense gaze that held no qualms over staring.

He was fine. He really was, and, after a quiet minute to take all this crazy shit in, Sanji asked, "So this…" He gestured over his chest again. "It's really okay?"

This time, the guy looked down at his own chest, poked at the wound for a second before shrugging and replying with a nod.

"Well, I'll be damned," Sanji muttered, then leaned back on a palm and sighed. "I'm Sanji, by the way. I helped bring you here and-"

He trailed off, seeing the wide-eyed look of shock that had come across the merman's face, his tail, previously floating up at the surface, quickly dipping back down in surprise.

But over what? Sanji didn't know.

Maybe the guy didn't understand him, so he tried again, stating more simply, "My name is Sanji," hoping it would get his point across.

The merman stared at him for another long moment before he looked away, brow drawing in and shoulders slumping, almost as if letting out a sharp breath despite not even breathing air.

But eventually, he slowly brought eyes back to Sanji's face.

"I'm...Zoro…" he replied, pointing at himself briefly.

"Zoro…" the blond repeated, then cracked a smile at the insane mythical freak of nature that currently bobbed before him, looking a little less ferocious than before and much more like a sheepish human, for whatever reason.

"Damn," Sanji said with a chuckle, still grinning. "It fits."

* * *

 _Author's Note_ _: Can't link here, but full credit to an old drawing, entitled "Mer-Strawhats," by SybLaTortue on deviantART for the idea to make Zoro a tiger shark merman._


	2. Failed Migration

Sanji was fortunate enough to have a job that excited him, a job that afforded him the chance to wake up every morning and _want_ to get to work, _want_ to experience the adventures of the day, that always varied. The ocean, and its wildlife, were unpredictable, and Sanji absolutely loved this fact.

But it wasn't every day that he felt no irritation or regret about hardly sleeping at all, about passing out on a chair _in the lab_ , and still feeling awake and eager enough to want to hurry to work the next day.

He always started his days early, sometimes arriving at the lab before five in the morning to check on the animals, take care of a few feedings.

However, it was four thirty in the morning, and Sanji was just getting _home_ , creeping in the door of his and his dad's small bungalow so as not to wake him.

He wasn't staying for long. He just wanted to shower, get some fresh clothes on, maybe make himself a cup of coffee before hurrying right back to the lab next door.

Because that's what he'd told Zoro he was going to do.

Zoro.

The fucking _merman_ currently staying in their large species rehabilitation tank.

He honestly didn't know how his dad had managed to even _leave_ the lab that night.

Sanji was practically knocking over chairs and stubbing toes on end tables as he stumbled through the small living room in the early morning darkness to get to his bedroom, overcome with a rather fantastic sense of wonder about the world.

Thankfully, the bungalow was split, with the two bedrooms down separate short hallways on either ends of the living room and kitchen area. And his old man could be a pretty heavy sleeper, so as soon as he made it to his room, Sanji didn't worry about being _too_ quiet. He was usually up at this hour, getting ready, anyway.

A rinse in the shower to at least get the previous day's seawater salt off him, and a quick shave, then it was back to his room to grab a clean outfit, nearly identical to the last pair of khaki shorts and polo shirt he'd had on earlier.

It wasn't the most fashionable, and he knew that, in another world, he'd much prefer to dress up nicely every day, but it was practical, so on they went, the khaki over a tight pair of wetsuit shorts he normally wore just in case he had to take a dip in the water, which he often did.

And which he was thoroughly _hoping_ he'd get the chance to do today, because as irritating as that damn merman was, he wanted to _study_ , dammit, for his _own_ benefit.

The more he thought about it, the more he knew they _shouldn't_ let the M.A.R.I.N.E.S. take him. There was no telling what they'd do to him, what conditions they would keep him in, and knowing that this merman was an entirely sentient, if slow and dickish, being, morally he couldn't let him be taken for study just like any other animal.

A quick ruffle of fingers through his hair, which he didn't bother to dry, checking himself over for a moment in the mirror over his dresser.

His job wasn't glamorous, and he certainly didn't look his best now, tired, dark circles under his eyes and hair a wet mop. Certainly not compared to the photos he'd stuck in the frame of his mirror, ones where he stood in a nice suit at his college graduation, another a silly selfie with Ace where they both actively _tried_ to look sexy. And pulled it off nicely, if ridiculously, Ace with his tongue out and a finger caressing his bare nipple, and himself leering with bedroom eyes at the camera, a fingertip between teeth.

Yeah, his dad was never allowed to see that one. But it made him crack a smile, so he left it out in the open, just below a strange piece of black netting he'd had to secure to the corner of the mirror with tape.

His eyes lingered on that, just for a moment.

It was netting he'd apparently been found in on the beach when he was a baby, and he didn't know why he kept it. It wasn't like he had any recollection of that time, always growing up with Zeff from that point on, but there was something about it. It made him remember his roots at the very least, made him appreciate the life he did have, because he likely wouldn't have had it otherwise...

A huff of breath and he shook his head, fussing with his hair one last time before heading out of his room, flipping off lights and moving to the kitchen so he could fix himself some coffee.

He waited by the sink as the coffee brewed, glancing outside where he could just make out, in the darkness, the slightly eerie outlines of the little grove of banyan trees out back, their sinewy roots draping down from the branches, reminding him of the time he, Ace, and Ace's little brother, Luffy, had tee-peed the trees outside the two's brother, Sabo's new apartment.

They'd run away and tried to hide in the bushes to film his reaction when he came home, but had been easily spotted.

As it went, he and Ace had also made out there not long after. They'd had to take advantage of Ace's time off from the base, after all.

Sanji had a smirk on his face when he checked his watch, noticing that it had only been a half hour since he'd left the lab.

He'd told Zoro an hour, but honestly, how the hell was a fish supposed to tell time? So he didn't feel bad in the slightest about hurriedly pouring coffee into a thermos, slipping back into his water shoes, and heading out much sooner than expected.

Out he went, from the bungalow's front door, across the square flagstones, with only the light of tiny lanterns on the ground near the path leading his way back to the lab.

Of course, it was only a short walk before he reached the bigger building, the motion-activated lights over the heavy white doors flipping on, instantly creating spider-like shadows from the palm trees that swayed gently in the warm breeze.

He lifted his lanyard to scan his way in, and then it was through a small entrance hallway, the wetness of the floor already indicating what was beyond the second pair of doors he scanned through to finally enter the massive rehabilitation room again.

As eager as he was, he decided to pretend he wasn't, going through the rounds for the turtles first.

Thankfully, the turtles were all they had in their care right now, a few green sea turtles, and one massive loggerhead that had eaten a plastic bag and nearly died several weeks ago.

A healthy seaweed mix for the green turtles that didn't take long to prepare and was particularly rewarding to watch as the three in the tank, whom he'd had fun naming Lettuce, Cabbage, and Spinach, slowly but vigorously devoured their breakfast.

They were young and sickly when they'd first arrived, so it was great to see the three girls had an appetite again.

Then it was a shrimp breakfast for Beefsteak in the adjacent tank, the turtle named for his flat, thick shape and his brown color. Sanji had suggested 'Patty' originally, but the real Patty had protested grumpily, so Beefsteak it was.

Part of him wondered, as he leaned over the edge of the shallower tank to watch the loggerhead chomp his massive jaws around the surface of the water, if Zoro could hold a conversation with these guys.

It was an exciting prospect, but again, he suppressed that excitement when he finally stepped up to the window of Zoro's tank, sipping at his coffee and peering through to the water that glowed blue beyond, a source of light itself when he had yet to turn on the harsh fluorescents overhead.

What he found was the merman seemingly passed out again, floating beneath the surface with his eyes closed and body relaxed….but with arms crossed behind his head as some kind of unnecessary pillow and a stream of bubbles escaping his gaping mouth now and again, almost like some unsightly snoring.

Sanji rolled his eyes, hiding a smirk behind his thermos at how ridiculous the whole situation was, until an idea struck him.

Maybe he couldn't have a chat with the guy right now, and with that angry red slash still marring the skin of his torso, Sanji wanted to let him rest a bit, if only to give his inhuman healing abilities a chance to show off what they could do.

But he still had a smirk on his face when he abruptly turned and walked over to one of the lab benches, opening a large black case on the table to pull out an expensive underwater camera, big and cumbersome, but fucking _amazing_ at capturing stills, something he absolutely wanted to do now.

He checked the charge on the battery, threw the strap over his neck, and left his coffee there to cross back to the tank with the device, hefting the long lens into one hand and pressing an eye to the viewfinder to adjust the zoom and focus.

The window was clean and clear, so he was able to get a few preliminary shots, the satisfying click of the shutter capturing a full-length view of the merman, then some close-ups of his tail, moving up his body to his human half.

It was normal for them to photograph any wounds or injuries on the creatures they found, to help track their progress and provide reference for future rescue missions as well. And this was what Sanji told himself when he may or may not have spent a little longer than usual on that chiseled chest and abs which were _injured_ , okay?

He couldn't get all the shots he wanted though, couldn't properly see his fins, or his gills, the scars and jagged tears along his caudal fin.

The blond lowered the camera with a huffed exhale, a finger tapping against the ridges of the lens for a second.

But then he decided. The best way to get the shots he needed, _for science_ , was to get right in the water himself.

So he hurried to another bench along the wall, opened a metal drawer and grabbed a pair of goggles, the large kind that covered both eyes and nose. Then he circled the tank to the platform, climbing up the metal stairs quietly, because for some reason this felt a little intrusive, like he was going to barge in on the guy sleeping and start taking photos of him and...

Well, that was literally what he was doing. And considering the merman had a perfectly human mind, he was, thus, capable of getting very pissed and creeped out, as Sanji had already seen.

But the blond also decided he didn't fucking care. Let him get mad. Sanji was pretty sure he could kick a fish's ass or….tail? Whatever. If he needed to, in any case.

He set the camera down on the platform briefly to pull off his shirt and khaki shorts, leaving him in nothing but his wetsuit shorts and water shoes.

Normally, he'd go for a full wetsuit, but he knew this tank was heated, and it would only be for a few minutes anyway.

So on went the goggles, and he carefully slid himself into the water as silently as he could.

His heart fluttered a little faster, as it always did when he entered the water with a predatory species, and goosebumps prickled at his skin. The water wasn't freezing, but it still wasn't ideal _swimming_ temperature for a human.

Still, he grabbed the camera off the platform and slung the strap over his neck again, the weight of the device already making it difficult to stay afloat as he was, so he kicked legs up and swam on his back until he treaded water close to where Zoro was sleeping.

Now or never, he figured, so he took a deep breath and let the weight of the camera help him sink faster until he found himself fully submerged in the tank with the merman floating before him.

He'd pulled the guy out of the water. He'd _felt_ his weight and size, but seeing him in his natural habitat was somehow a little more intimidating than having his unconscious form flopped out on the deck of a boat.

A second to take in the moment, then he got to work, sinking lower so he could finally document those fins, the ringed and spotted pattern of his skin, unique to any tiger shark, and clearly to him as well.

He surfaced for a breath, then dove back down several times to photograph the little markings and scars that usually indicated fights with other fish, tried to capture how his gills worked, how red they were compared to the green of his tail.

It was all typical shit until he found himself fixated, once again, on Zoro's human half, the three tattooed rings circling his right bicep, how damn _green_ his hair was, almost seafoam color, and it sure as hell appeared to be natural.

And then he found himself lowering the camera, hovering there in the water beside the merman, watching his sleeping face, and feeling the sudden urge to reach out and touch him, to stroke fingertips over his angular jaw just as he had to Ace on nights they'd spent together.

He hadn't even been conscious of the fact that he'd reached out to do just that, all scientific study forgotten as fingers sought to perform a different kind of study….one that was far more embarrassing and perhaps violating should he be found out.

Maybe it was foolish, but he didn't care, just let his fingers touch down on the man's cheek, determined to use these last ten seconds or so before he needed air to gently explore.

Until a hand darted out, clamping down hard on his wrist, and then dark, nearly pupil-less eyes shot open to fixate on him for a split second.

Sanji's eyes widened in surprise, a muffled noise of shock leaving him, along with a flurry of air bubbles.

Zoro smirked.

And that was the only warning Sanji got before the merman pushed a hand onto the blond's chest and bodily slammed him down against the sandy floor of the tank, a sharp-toothed grin on his face as Sanji's back displaced a cloud of it.

Sanji immediately struggled, driving a knee up to ram into Zoro's stomach, hands reaching up to shove at him, though Zoro kept his forearm firmly pressed against Sanji's chest, his other hand pushing his shoulder to insure he stayed down.

The shark-man grinned, moved the rest of his body up a bit to avoid Sanji's futile kicks.

He kept him there for far longer than he should, until Sanji's kicks and punches started to become far more frantic and panicked, bubbles flying from between tightly clamped lips with greater speed.

Only then did he reach out, remove the camera from around Sanji's neck, and release him, the blond immediately scrambling to kick off the bottom of the tank and shoot to the surface.

A loud gasp as he broke it, followed by desperate coughs and splutters, his heart pounding and his chest burning as he flailed himself over to the platform so he could hold himself up more easily.

As soon as Zoro's head popped up beside him, he jolted and lashed out with a foot, connecting with the merman's chest and sending him flying back in the water a few feet.

"Get the hell away from me!" he huffed out, using the opportunity to heave himself up on the platform and hopefully out of Zoro's grabbing range should he try and drag him under again.

"What the fuck is _wrong_ with you?!" Sanji panted as he rolled over onto his back, pulling the goggles off his face and tossing them aside.

A few more heavy breaths and coughs, then he rolled over to face the water again, to glare at the fucking _asshole_ of a merman currently drifting smugly in the water, examining the camera he still held.

"Were you trying to _kill me?!_ 'Cause I'll have you know! Shark fin soup is a thing! And shark finning is horrible, but I think I could easily make an exception for _you_ , bastard!" Sanji screeched, wiping a hand over his mouth when water from his drenched curtain of hair gave him a salty mouthful before he reached up to irritably wring at it.

He'd completely overlooked the fact that Zoro likely couldn't understand him when he went on a rant like that, but it was his _tone_ , at the very least, and the feral snarl on his own face.

The merman hardly appeared to be listening though, still fiddling with the camera, and when he brought the thing to his eye and ducked beneath the water again, Sanji scrambled to the edge of the platform.

"Hey!" he called. "Bring that back! You break it I _will_ sell you off to a circus to pay for it, dammit!"

But then Zoro popped back up again, this time with the camera aimed straight at Sanji's face, the merman snapping a photo that instantly prompted the blond to scramble to grab it from him.

Zoro slid out of reach though, somehow knowing to press the review button to look at the photo, which only led to a bout of snickering at the ridiculous capture.

Sanji groaned loudly, and only then did the merman look up, as if noticing Sanji's presence for the first time.

"Three," he said simply, holding up three fingers at the blond and grinning.

"Three?" Sanji huffed with exasperation. "Three what?"

It took Zoro a second to reply, brow furrowing as he seemed to search for the word before he finally replied with a proud, "Minutes!"

A beat to process what Zoro was trying to say, which was apparently too long for the merman to wait because he rolled his eyes and jabbed a finger at the blond to clarify.

"You…...Water….Three minutes," he said slowly, then gave a sarcastic round of applause that was enough to have Sanji practically throwing a thrashing tantrum up on the platform.

"Shut up!" he shrieked. "Could've gone longer if _someone_ hadn't tried to _unexpectedly drown me!"_

He tried to compose himself though, unwilling to let a dumb fish-man fluster him.

 _Yes,_ he was good at holding his breath, thank you very much, but it was kind of necessary sometimes, working the job he did.

"How long were you awake," he demanded next of the merman, and when Zoro tilted his head to the side, Sanji almost wondered if they'd have to go back to stupid charades again in order to understand each other.

But then the look on Zoro's face turned downright evil, and he swam right up to the edge of the platform to answer, "Before _this_ ," reaching up to give an exaggerated stroke to Sanji's face.

In turn, Sanji's cheek practically exploded with a powerful flush that even a deep scowl or the cool rippling patterns reflected on his skin from the water below couldn't hide.

"I'm a _biologist,"_ he, thankfully, recovered with. "It's my _job_ to research weird shit like _you!"_

A growl and he leaned his face in closer to Zoro's, just to show he wasn't intimidated _or_ pathetic, despite being sopping wet and mortified.

"Speaking of which, _give me my camera_ ," he emphasized, though Zoro obediently lifted the device and slid it back onto the platform, propping elbows there casually a second later.

Sanji muttered some curses under his breath and sat himself up, crossing legs under him and taking the camera to check for damage before setting it aside.

It was a little odd. Considering how everything about Zoro was foreign to him….Zoro really didn't seem too perturbed about where he was, or about the abnormalities in _humans_ compared to him.

Sanji would have expected a fucking _merman_ to be, if not fearful, curious about _everything_. And while Zoro certainly seemed annoyingly curious about him as a person, nothing else seemed to be baffling him as much as Sanji would have assumed.

He filed that thought away for the time-being though, because he had other business he wanted to attend to, namely the countless questions he wanted to ask the merman. So he got to his feet, ordered Zoro to "Stay," again like a dog, then started to walk towards the stairs, shoes squelching.

He'd just made it to the top when there was a splash behind him, and he immediately turned around to see Zoro had pushed himself clear out of the water, now lying with most of his body sprawled on the platform.

Sanji stared at him for a long moment, eyes narrowing suspiciously, especially when Zoro propped up an elbow and rested his chin there.

"What are you doing…?" Sanji asked slowly, only for Zoro to shrug and shoo him off with a wave of a hand.

For the fiftieth time, Sanji scowled. He locked eyes with the merman as he slowly crossed over to snatch up the camera, just in case Zoro tried to pull anything else, before backing up again just as slowly towards the steps.

He left the weird guy where he was, knowing he was fully capable of getting himself back into the water, and he walked over to the lab bench again to set the camera down.

From there, he found his laptop plugged into a wall, powered it up and opened a new Excel document.

Quickly, he pulled out his notebook he'd left in the desk drawer, flipped to his notes about Zoro from earlier, and transferred them over to the computer, just for better security.

The pictures and videos he'd just taken could wait, because now he was going to get some answers out of Zoro, whether the idiot liked it or not.

So eventually, he slipped his laptop into a protective waterproof sleeve, should any stupid algae-heads go splashing about, and he brought it back over to the tank, ascending the stairs to find Zoro still flopped there out of the water, looking, if not uncomfortable, certainly bored.

The blond noticed Zoro's gaze was fixed on something behind him, so he glanced back and deduced, with some surprise, that Zoro was eyeing the clock on the wall.

"Still don't know how the hell you know what time is, you damn fish," Sanji muttered, settling himself down to sit beside Zoro again with his laptop.

Zoro ignored him, just kept staring at it, and it was annoying to the point that Sanji very nearly said something, shoved him back in the water.

But then, suddenly, Zoro's face lit up in a triumphant grin and he did the work himself, sliding back until he was perched there with elbows resting on the platform again.

" _Four_ minutes," was all he said to Sanji, who blinked at him for a moment before he _got it_ , and then he lashed out with a foot to try and kick Zoro's face in.

" _Fuck_ you!" Sanji cursed, just before the merman caught the sole of his shoe…..with his _teeth_.

One prolonged screech, some mad flailing, and one shoe at the bottom of the tank later, Sanji was left to sulk as the merman yet again watched him like the smug-ass bastard he was. He was _really_ beginning to see that this guy wasn't fully human after all.

And that was precisely why he stubbornly set up a new document on his computer so he could type out Zoro's answers.

"Alright, look. I have questions. So answer them, okay?" he said, looking up at Zoro grumpily. "If _you_ have questions about anything, that's fine. We can alternate."

He seemed to lose the merman though, so he sighed, pinching the bridge of his nose. Ultimately, he pointed to himself and said, "Question," then pointed at Zoro with, "Answer."

He repeated the sequence, starting with Zoro as the question, but he'd barely gotten another word out before Zoro unexpectedly burst out laughing, full-blown laughter the likes of which he hadn't seen from the merman.

It caught him entirely off-guard.

"What the hell is so funny?" Sanji huffed, only to have Zoro point at him, then gesture to his own eyebrow, making a swirling motion towards the center.

" _Question!"_ he cackled, and Sanji's jaw dropped indignantly, having _never_ met a nitpicky asshole of this caliber in his _life_.

He very nearly rose to the bait of Zoro's teasing again, until a thought struck him and he managed to ask, "Wait - can you _read?"_ because if Zoro could associate a swirling pattern, which most certainly did _not_ exist on his face, with a question mark? Surely that had to mean he recognized the symbol.

Zoro's laughter had, thankfully, died down, though the merman still grinned cheekily, those jagged teeth of his on clear display.

"Alphabet," he said. "Name….Small words."

Sanji's eyebrows rose, admittedly surprised. He supposed maybe there was evidence of the alphabet underwater, in shipwrecks or even garbage, but how Zoro could recognize them as _words_ , as _language_ was beyond him.

It took him a second before he realized he should be recording this, so he quickly typed out his question, followed by Zoro's response, word for word.

"How though?" he asked next. "I mean...you can read and speak a little of our language? How?"

"Learned," Zoro replied with a shrug, not answering his question in the slightest, and it showed when Sanji immediately rolled his eyes.

"From who? On your own? From _humans?"_

"From teacher," Zoro answered, looking confused, as if Sanji should know this already and was, thus, an idiot. "Human teacher."

Then he settled himself a little closer and pointed at himself.

"My question," he grunted, seemingly ignoring the fact that Sanji was still reeling from his previous answer.

A _human teacher?_ Who? How? That would explain why the human world wasn't surprising him, but it meant humans had been in contact with merfolk before!

Sanji's head spun as Zoro asked, somewhat awkwardly as he struggled for the words, "How old - are you?"

"What-? I - twenty-four," he stammered, then shook his head. "Back to mine! What _teacher?_ How is this even-?"

"Robin," Zoro interrupted, now looking at Sanji like he was most definitely crazy. "Where is she?"

"Robin? Robin who? I don't know any-"

"Robin Nico," Zoro shot back matter-of-factly, then he shot Sanji a condescending look, quirking a brow.

" _New?"_ he asked, again indicating the blond.

"No!" Sanji countered with indignance, though, strangely, that name sounded familiar…. "Robin...Nico?"

"O.H.A.R.A?" the merman insisted. "This is….West Blue?"

"No. We're in _East_ Blue…You're at B.A.R.A.T.I.E..." Sanji answered slowly.

And he made the connection in his mind, eyes widening in the same moment that Zoro's had, a look of complete dread coming over the merman's face, contrary to his usual cockiness.

Even more surprising, Zoro pushed off the platform, swimming away, far out of reach of Sanji, and for the first time, he actually exhibited something close to what Sanji had expected his initial reaction to be upon discovering where he was.

He wasn't sure he could call it _fear_ on the shark-man's face, but it sure as hell was apprehension.

"Phone," Zoro demanded suddenly, bringing a hand up to gesture at his ear for emphasis.

The rest of Sanji's questions slowly retreated to the back of his mind now that he'd realized too.

Robin Nico. _The_ Dr. Robin Nico. President of O.H.A.R.A. and how the _fuck_ had the name slipped his mind?

And Zoro knew her? Zoro had been in contact with O.H.A.R.A.?

Suddenly, Sanji began to wonder if the reason the West Blue association had broken off from the M.A.R.I.N.E.S. was swimming right in front of him…

" _Phone,"_ Zoro said again, now holding out a hand insistently despite the distance he maintained, and Sanji narrowed eyes, sitting back and setting his laptop on the platform.

But he did rummage in his shorts pocket where he'd stuck his earlier, holding it up almost as a peace offering, tapping his passkey to unlock it, then sliding it across the platform towards the water.

Like practically everything else he owned, he had a waterproof case on the thing, but he noticed how Zoro swam over and was careful not to drop it in the water. He was even careful not to let wet fingers touch it too much, wiping his hand on Sanji's shirt first, much to the blond's annoyance, before flicking a thumb over the screen like he'd used a smartphone a million times before.

The illusion was blown eventually though when he couldn't locate the call screen, so he huffed and held it back out to Sanji, looking uncharacteristically nervous as he made a vague gesture that indicated punching numbers in.

Sanji got the message, so he opened up the keypad for him and handed it back.

Zoro made a small grunt in return, then began tapping out a number, bringing the phone to his ear a second later.

Was he calling O.H.A.R.A.?

Sanji had no idea, just that the longer it took for someone to pick up, the more visibly upset the merman was beginning to look, his free hand lifting to run over his hair, down the back of his neck, teeth biting at his bottom lip every now and then.

Fuck. Did he really think something bad was going to happen to him here….?

It kind of hurt, for some reason, to think that Zoro didn't trust him, or if he had, that his trust had been so easily shattered simply by learning where he was.

He must have known something. If not about Sanji's organization specifically, then about East Blue in general, potentially the M.A.R.I.N.E.S. as well.

This was absolutely solidifying the fact that he did _not_ want to turn this guy in.

"Robin!"

Zoro's voice interrupted the blond's thoughts, calling Sanji's eyes up to Zoro's face as a look of relief came over his features when the person on the end presumably answered.

A short silence, then Zoro started to stammer out, "Uh - now - East Blue - I - thought it - thought I was-"

He let out a frustrated growl, and, to Sanji's _complete_ surprise, suddenly switched to an entirely different _language_ , a language he had _never_ heard in his life but that Zoro seemed to be completely comfortable with as he spoke with perfect fluency and speed.

Zoro bit out hard consonants, drew out longer vowels to a person that clearly must have understood him, and his gaze flicked to Sanji several times throughout his conversation, enough that Sanji began to get the feeling that he was, or was soon going to be, the subject of the call.

He didn't have to wait long to find out, however, because he soon found the phone thrust his way.

Sanji stared at it for a second until Zoro jerked his chin expectantly, and he managed to take the device despite his shock over the situation.

"Hello," he answered tentatively, eyes still on Zoro. "This is Sanji Red with B.A.R.A.T.I.E."

A calm, and slightly amused female voice answered him.

" _Oh, Dr. Red's son, I presume?"_ the woman asked, and Sanji could practically hear the smirk in her voice. _"I'm very glad to speak with you. This is Dr. Robin Nico. President of O.H.A.R.A. I must thank you for taking care of Zoro~"_

"I-"

Despite speaking to a highly respected colleague, the blond found himself stammering for words in the face of just how damn _casual_ this whole thing was.

He still had a _merman_ floating here, and while maybe his few hours spent with him had served to normalize the situation a little, to suddenly have someone he never spoke to seem completely _in on this?_

"Um...with all due respect, Dr. Nico," he eventually huffed out. "Would you mind explaining just what is going on?"

A chuckle on the other end.

" _Of course, but before I do, I must ask what your intentions are with Zoro~"_

It was dumb, but the way she asked it automatically had Sanji's ears heat, gaze flicking sheepishly towards the merman as if he could pick up on the subtext.

But Zoro's brows were drawn in, and he looked just as perturbed as before, though he'd swam closer again, no longer looking quite as skittish.

" _Are you the only one who's seen him?"_ Robin was asking, and Sanji shook his head, looking away from Zoro's intense gaze to focus instead on his lap.

"No, it's - the four of us picked him up off the Shimotsuki Reef. Me, my dad, and our guys, Patty and Carne too. We haven't called anyone yet. And frankly, I'm not looking to. I told my father this, and I think he's in agreement."

" _I thank you for your decision,"_ Robin replied, sounding pleased. _"Is he doing alright? He told me he had a run-in with a propeller."_

This confirmed Sanji's suspicions. Dr. Nico _could_ understand his language.

"Yeah, um…" he replied, not liking how much he was stuttering, but dammit, this was _insane._ "Much better. I was worried in the beginning, but he's had something to eat, and the wound is looking better already. But - Dr. Nico. You can _understand_ him?"

" _Why yes,"_ Robin answered, as if it were a completely normal answer. _"I've been working with him since he was ten years old, after all~ I'm afraid he hasn't kept up with his studies of our language, however, so I apologize for any difficulty you've had communicating."_

Sanji couldn't help a noise of disbelief, and he leaned back on a palm, staring straight ahead now as he tried to comprehend all he was being told.

Robin seemed to sense his complete bewilderment though as she continued, _"He was on his way to our center for a lesson, but lost his way. Even with his shark half, it has never afforded him many gifts in the migratory department~"_

"Wha - lost his way? All the way to _East Blue?"_ Sanji yelped, this time fixing his gaze on the idiot merman, who seemed to pick up on what he was talking about, and scowled.

" _Well, his colony hails from East Blue,"_ Robin explained. _"Normally, we know to expect him late, but I must admit, we've been rather worried-"_

"Hold on - a colony? There's - there's _more?!_ " Sanji interrupted, and though he was sorry for his rudeness, he _seriously_ felt like he was missing something here. "Dr. Nico. He is a _merman!_ I - I'm sorry, but - you're talking about this like it's - some kid late for his piano lesson, but - this guy is _half shark!"_

He gestured towards Zoro as if she could see the sulking bastard who'd clearly tuned out the conversation altogether when he lost hope of following.

Sanji heard her gentle laugh.

" _Yes,"_ she admitted. _"I suppose this must be overwhelming if he is the first of his kind you've encountered. Perhaps, once he's feeling up to it, if you or your father would be so generous as to escort him to our center, we could discuss this more? If not, I could arrange for one of our boats to pick him up~"_

Sanji ran a hand back through his hair, closing eyes for a minute as if it would help him process this easier.

"Um….no, I - we can probably - make it out there today. I just - gotta check with everyone else," he said, bullshitting a little because he had no idea if they could.

The journey to the west islands of the archipelago was a good five hours in favorable weather conditions. But dammit, this was something they _needed_ to do. All other work could wait.

" _Great. Please feel free to save my number in case you need me. Though your father also knows where to contact me,"_ Robin replied before adding, _"And I do apologize. Zoro can be a bit of a handful at times, but I'm happy you two have met. I think it's been a long time coming~"_

Sanji had no idea what she meant by that, a strange _knowing_ tone to her voice, because he could only remember meeting this woman once, and he'd been much younger, in high school, he thought.

It was a weird thing to say, but then again, Dr. Nico seemed to be a bit on the eccentric side.

Unwilling to fight the matter now, the blond merely sighed, even cracked a small smile.

"Yeah, well, I've already dealt with him pullin' all kinds of stuff. Just needs a bit of discipline is all. Nothin' I can't handle," he assured, and his smile grew, hearing her understanding laugh in his ear.

" _Then I'll leave him to you,"_ she replied, and he nodded, falling more comfortably into his habitual professionalism now that he had actual business to attend to.

"One of us here will be in contact probably within the hour about the transport," he said. "I'll go ahead and assure you we'll be setting sail by seven at the latest."

" _Wonderful. Thank you. I look forward to seeing you. And please let me know if I can be of any more assistance. Though I already insisted Zoro not rely on me for translations. He could certainly use the language practice~"_

"I'll see what I can get to stick with him," Sanji replied, eyes drifting to Zoro one more time, who'd looked up with a questioning raise of a brow.

A few more closing remarks to the woman on the other end, then he hung up, making sure to save her number in his phone directly afterwards.

It was quiet, save for a faint splash that had him lifting eyes again to see Zoro swishing his tail anxiously about in the water, watching Sanji like a child on the receiving end of some punishment.

Sanji decided he liked that look on the arrogant fish's face.

"Would you relax?" he griped, tossing his phone back on top of his clothes and fixing Zoro with a look. "I don't know what the fuck's going on, but you don't have to worry. We're gonna bring you to O.H.A.R.A. and I'm not gonna let anything _bad_ happen to you. And neither is my old man or anyone. We don't pull that shit here. We're here to _help._ "

Zoro looked at him, _really_ looked at him for a long time, and Sanji could've sworn he saw something flash in Zoro's eyes, something that looked almost….emotional, before it disappeared.

The merman did allow a smirk to come to his lips again, indeed looking more relaxed, if not because of Sanji's words then because of his tone, rough, but comforting.

"Stop talking," was all he said pointedly, grinning and flicking saltwater right into Sanji's open mouth when he gaped in response.

"Get my shoe!" the blond growled, reaching out and shoving Zoro's head under until the merman swam down to retrieve it.

Maybe he smirked too, but only when Zoro wasn't looking.


	3. The Grotto

It was significantly more difficult to convince a now very conscious merman to tolerate the confines of a too-small holding tank on a tiny research vessel for a trip upwards of five hours.

However, Sanji wasn't sure how much of that was due to Zoro's consciousness, or simply due to Zoro being the stubborn irritant he was proving to be.

Even after apparently getting so damn lost he'd swum himself into a _propeller_ , the algae-head had insisted upon merely following their boat in the water, until Sanji had threatened a tranquilizer gun on him, an empty threat, but one that had worked.

It wasn't like the blond hadn't come prepared this time, to make the journey more comfortable for Zoro, who currently floated with a good third of his tail unable to fit in the tank, his arms and chin resting sulkily on a folded towel Sanji had laid out so he wouldn't burn his skin on the hot deck.

He scowled his whole way through Sanji and Zeff's travel preparations, but he didn't put up a fight when they moved him, which Sanji knew he could've had he not trusted them.

No, he was just being difficult to be difficult, even when they found themselves out on open water, cruising smoothly under the early morning sun, yet to rise high enough in the sky to make the weather sweltering, though that was sure to happen within an hour or two.

Patty and Carne had stayed behind to manage the research center, under strict orders to keep their merman situation entirely confidential. But Zeff trusted them, and Sanji did too, so it was actually pretty damn nice to be sailing alone with his dad, enjoying the wind in his hair and the spray in his face as Zeff bounced them along over the waves, setting the course from the small cabin.

It would have been even nicer sans the pair of inhuman eyes staring him down from the deck.

He should have ignored it, but dammit, the merman was too damn interesting for his own good, so Sanji pushed off the railing and stopped to pick up the small cooler bag he'd brought along with him, carrying it over towards the open tank and plopping himself down in front of Zoro.

The merman made a show of shifting uncomfortably in the water, glaring at Sanji all the while, enough that the blond rolled his eyes.

"Considering what all you can tolerate in the way of _pain_ and _injuries_ , you sure are a big baby when it comes to everything else," Sanji muttered as he unzipped the cooler bag, dissatisfied when Zoro's expression flickered through confusion. The idiot probably hadn't understood all of that.

He wanted the jibe to land though, so the blond glanced up and jabbed a finger at him.

" _Baby_ ," he said pointedly, and when the proper anger came over the merman's features, he smirked haughtily.

Zoro stammered after a second, most likely trying to come up with a retort but failing to find the right words in his second language.

Sanji just kept on smirking to himself as he finally pulled out a bottle of sunscreen.

He crossed his legs and scooted closer to Zoro, squeezing a bit of the lotion onto his fingertips.

"Hold still," he said, the only warning Zoro got before he reached the hand out towards the merman's face.

But Zoro flinched back away from his hand as if he'd just spread poison all over it, even giving a low inhuman hiss.

"Oh, come _on_ ," Sanji complained though, not intimidated in the slightest. "You're hanging out of the water this long, you're gonna burn! Do you wanna be a shark or a cooked lobster?"

Zoro merely growled again though and went so far as to try and force himself under the water, sliding his tail farther up onto the deck to curve into the tight space.

It didn't work, at least not without exposing his gills, so he had no choice but to return to his previous sulking position unhappily.

Sanji just looked at him smugly, brought his hand closer again, and grinned triumphantly when the merman let him rub the cool lotion over his cheeks.

"Wanted to swim…." Zoro muttered after a few seconds, gaze fixed longingly out at the trail of churned white water following the boat as it sailed.

"We're going faster," Sanji replied, fingers carefully avoiding the merman's eyes to smooth sunscreen over his nose. "We'll get there in half the time you would with your wandering."

Zoro just scoffed, seemingly unconvinced, sparking Sanji to take his chin in his hand while he was there, try to make the merman meet his eye.

He didn't, keeping his gaze firmly averted like a child, but still Sanji said, "What's your problem anyway? I said you could trust me, didn't I?"

For some reason, this was what finally brought Zoro's eyes sliding back to meet his, with enough lingering wariness that Sanji smirked and patted his cheek a little too roughly.

When Zoro scowled, Sanji took the opportunity to squeeze another dollop of lotion into his hand, transferring his gentle massaging to the merman's shoulders, which already felt warm from the brightening sun.

Zoro didn't stop watching him, something Sanji noticed, particularly when he leaned in a little closer to reach his back, hands working over the tense muscles.

He tried hard to resist the urge to look back at him, to allow their eyes to meet at such a close distance. Maybe his eyes would be fine, but he was starting to get a little worried about what his lips would do….

"Can't trust M.A.R.I.N.E.S…." Zoro said quietly, the look on his face serious when Sanji finally risked a glance.

"I don't work with them," he assured, to which Zoro quickly countered, _"East Blue-"_

"I don't!"

Sanji huffed a breath, this time meeting Zoro's gaze squarely, one hand still resting on the smooth skin of Zoro's shoulder.

"Look, don't go spreading this around yet because it's not official," Sanji said, flicking eyes to the cabin and lowering his voice so his father wouldn't hear. "But we've been talking about breaking B.A.R.A.T.I.E. from the M.A.R.I.N.E.S. Like O.H.A.R.A. We don't agree with what they do."

To this, Zoro's eyebrows raised, though they quickly furrowed, and for a second, Sanji wondered if he'd have to explain what he'd just said in simpler terms.

But then, Zoro said, "You do?" and it was Sanji's turn to look confused.

"Do what-?" he asked, just before Zoro gave a frustrated growl and shook his head, brow furrowed in concentration.

"Uhh-" the merman stuttered, but eventually amended his response to, _"Really?"_

Sanji couldn't help but chuckle a little at the guy's mistake before he replied, "Really. It's been a long time coming. We've been trying to get the funds and the support together so we can remain entirely independent with our-"

"You want - to help us?" Zoro interrupted.

And Sanji was surprised at the very human emotion that shimmered across Zoro's gaze, his chin lifting from his arms to look at Sanji with something akin to _hope_ , if that was even possible for a lout like Zoro.

Sanji knew nothing of his plight - of the _merpeople's_ plight. Hell, a mere twenty-four hours ago, he'd been entirely oblivious to their very existence.

He still had moments where he struggled to make sense of all of this…

A short laugh, not at Zoro's words, but more out of disbelief.

"I mean - of course, but - Zoro, you're the first - merperson or - whatever you call yourselves - that I've ever seen," the blond admitted, bringing his hand back to his lap finally. "I've always thought you were just - a-a myth."

And furthermore, that led him to another question he'd had floating around in his head ever since Zoro had shown knowledge of the M.A.R.I.N.E.S….

"How do you even - _know_ about the M.A.R.I.N.E.S.?" he asked, in the face of a truly shocked expression on Zoro's face that seemed to be there thanks to his previous comment. "How much do you know about what they-?"

"Eggplant."

Sanji looked up to find Zeff with his head poking out the cabin door, his dumb Western-style hat that he always insisted on wearing casting a tall shadow on the deck below.

Annoyance rose within the blond for the interruption, his muttering of, "What, geezer," enough to illustrate that.

"A word," was all Zeff said to his son, but it was followed with an odd, almost challenging look to Zoro, one the algae-head furrowed brows at in return before Zeff ducked back into the cabin, his stocky form visible through the rounded windows.

Sanji made an irritated noise, but planted a foot on the ground and got to his feet smoothly, despite the rocking of the boat, leaving the sunscreen bottle on the folded towel before Zoro.

"Finish your arms," he said to the merman with a jerk of his chin, then reluctantly crossed the small deck to swing into the cabin himself.

"Make this quick, old man," he muttered. "Someone's gotta make sure he doesn't roast out there."

But Zeff ignored him, merely stood at the silver wheel, his gaze staring fixedly out the window at the open ocean before him, silence persisting, save for the whir of the motor and the slight jingle of the silly little hula girl figures Sanji had tied to one of the metal bars above the window a few months ago.

"Whatever we see or hear today," Zeff finally grumbled, voice low. "We don't breathe a word of it."

Sanji huffed a breath, sticking a hand on his hip.

"Well, obviously. The M.A.R.I.N.E.S. find out and-"

"Not even to Patty and Carne."

This gave Sanji pause.

Not tell their trusted colleagues? Who'd been working with them, dedicated themselves to the cause for nearly fifteen years now?

"Why?!" he shot back, through a scoff. "It's _Patty and Carne!_ They're not gonna-"

"Some things are best left covered, brat," Zeff growled in reply. "Be glad I'm even lettin' _you_ come along."

"But-" Sanji stammered, but it was the way Zeff had said that, how calm and almost...expectant, he seemed, for what was to come.

"Hold on…" he said slowly, feeling a sudden surge of anger and hurt fill him. "Did you - You _knew_ about this, didn't you! You knew about them? You knew O.H.A.R.A. was in contact with them?!"

To that, Zeff merely gave a heavy sigh, still watching the horizon line ahead of them.

"Of course I knew, eggplant," he muttered. "I've been studying these oceans since before you were born-"

"Why didn't you tell me?!"

Sanji's breaths quickened, and he found himself having to resist the urge to grab the old man and kick his ass. It explained it. It explained his father's lack of real surprise over this whole ordeal, why he'd merely grunted and agreed to help transport Zoro to West Blue when Sanji had mentioned it that morning.

But his stoicism was infuriating, despite having had an answer to Sanji's desperate question right away.

"Because I knew you'd find out on your own one day," he admitted grudgingly. "And until then, I didn't want you chasing them. Humans have no business interfering in the lifestyle of the merfolk-"

"And yet, you've gone and left O.H.A.R.A. to their business-!"

"What _they're_ doing is necessary," Zeff grunted, the old man scowling when he spared a glance at the disdain on Sanji's face. "Brat, I'm not looking to argue this with you. I'm not saying you can't learn more. But I do not want you getting involved more than you should. It's too dangerous."

There was something strange about Zeff's response, and maybe it was the fact that his father had kept all this from him for so long, but Sanji couldn't help the feeling of suspicion that wouldn't leave him. The feeling that Zeff knew far more than he was even letting on right now.

Did he expect his father to tell him every damn thing in the world? No. But, as a scientist, did he expect the man to share findings as monumental as this? Um...only a _lot_.

This was why he very maturely repeated the man's last sentence in a mocking voice.

 _"It's too dangerous?"_ Sanji grumbled. "For who! Don't go all King Triton on me, geezer! You know I'm not gonna do anything to hurt them - and if I wanna know more, you can't stop me! Unless you want to give me a proper explanation for why it's _so damn dangerous."_

He rose brows at his father expectantly, unsurprised when the older man merely stood in silence. It was enough to have Sanji rolling his eyes after a moment.

"Yeah. Didn't think so," he muttered, then pushed off the control panel to head towards the door. "Now if you'll _excuse me,_ I'm gonna go fraternize with _danger_."

Turning on his heel, he did his best to storm his way from the small room, even though it was really only another few paces before he was sitting himself down on the hot deck in front of Zoro again with a scowl firmly etched on his face.

"He _knew_ about you!" Sanji griped out loud for no particular reason other than wanting to rant. "Or - about your kind, but - he knew! And he never told me! Why! What the hell! If he thinks that-"

Sanji paused though, noticing that he didn't seem to have the merman's full attention.

The guy had his forehead pressed against his arms, still resting on the deck, and Sanji wondered, for a second, if he'd fallen asleep. Eerily, but unsurprisingly, there was no movement in his shoulders or chest to indicate his breathing, at least not as a normal human would.

"Hey. Mossball," Sanji tried, and felt a stupid rush of relief when the merman made a disgruntled sound in reply, though he didn't lift his head.

Well, he wasn't dead, Sanji thought as he let out a breath, but he still reached out to push the merman's head to the side, much to Zoro's irritation, getting a look at his face, which was flushed and felt hot and dry to the touch when he pressed the back of his hand against Zoro's temple.

Shit. Apparently he'd have to be more attentive than he'd previously assumed.

"Hold on," he muttered, and pushed to his feet, crossing the deck to grab a small bucket secured beneath one of the benches along the side of the boat.

He brought it back over to Zoro, sat down so he could dip it into the churning water of the tank….and dump its contents directly over Zoro's head, effectively drenching him and plastering his hair to his forehead ridiculously.

However, unlike any _human_ Sanji knew, the inevitable protest that should have resulted from the thorough soaking didn't come. In fact, Zoro just sat there, no sputtering or moves to dry himself off.

"Better?" Sanji asked after a moment, and watched Zoro until he nodded.

Sanji gave a satisfied nod in turn, then dunked the bucket again to slosh a more continuous flow of water over him.

"Anyway, were you even listening?" Sanji huffed, eventually passing a hand through Zoro's wet hair so he didn't look so stupid with it sticking to his face. "The geezer knew about you merpeople all this time!"

Zoro's eyes were fixed on the cook for a long minute before he simply shrugged.

"He's not stupid," was all Zoro mumbled, something that very nearly landed him with a bucket smashed over his head.

" _I'm_ not stupid!" Sanji screeched in reply. "He didn't _tell_ me! That doesn't make me stupid! Don't tell me he's been giving you secret cooking lessons right along with Dr. Nico-!"

"No," Zoro replied, then paused before he added, "I never see him."

The blond made an annoyed sound, slamming the bucket down on the deck and throwing arms over it so he could lean in closer and glare at the merman.

"You never see him or you've never _seen_ him?" he grumbled, not usually an asshole about grammar, but he sure as hell would be when it came to this idiot fish.

This only brought a look of complete confusion onto Zoro's face, and he scoffed, scratching fingers at the back of his head for a second before he gave a somewhat helpless shrug and finally said, "First time…?" with some degree of hope that Sanji would understand him.

"So you've never _seen_ him," Sanji muttered, a little relieved that his dad _hadn't_ been secretly part of this whole operation. Despite what he'd just said, a revelation like that _definitely_ would make him feel stupid…

"Only know….B.A.R.A.T.I.E…." Zoro was saying, turning himself around in the water with some degree of difficulty so he could lean elbows back on the ledge and float torso-up for a time. "Who is he…?"

Sanji's eyes had drifted to the red line across Zoro's chest, now on its way to looking like a healing scar. He'd always known sharks healed fast, but to see it happen on a semi-human was, admittedly, pretty damn fascinating.

"My dad…" Sanji replied, eyes fixed at the water lapping up over the merman's abs. "Also the head of our research center, unfortunately…"

"Your _dad?"_ Zoro replied, and it was the slight derision in his voice that finally distracted Sanji's gaze and brought it back to his face.

"Yeah. You know. _Dad?"_ But when Zoro continued looking at him like he'd lost his mind, he rolled his eyes. "Fine. _Father_. Damn. Dr. Nico was right. You don't know shit."

Zoro didn't rise to the bait, however, just quirked a brow at the blond, then turned his head to glance up at the cabin window.

When he looked back at Sanji, he asked, "Your mother…?"

Despite his best efforts, Sanji's expression couldn't help but darken ever so slightly. These were subjects he hardly ever talked about, not even with his friends. Why would he? He was happy and content with the stupid old man. There was no use dwelling on the past.

"Don't have one," he answered simply. "My real parents dumped me as a baby. They didn't care, so why should I. Now, enough damn questions! I'm the one who should be interrogating you, anyhow. And come to think of it, you're a shark, so your parents probably ditched you too."

Zoro nodded absently and shrugged, though his brow was still furrowed, almost as if he was still processing everything Sanji was saying to him.

Of course, all of this raised yet more questions about how merpeople were born, but Sanji figured that was a conversation best directed towards Dr. Nico or someone with the adequate scientific knowledge and _language skills_ to explain such a thing.

The dumb merman still looked lost in thought for too long for Sanji's liking, so he used the bucket to splash some water in the merman's face, just to try and irritate him back to his snarky self.

"Last night you asked how old I was," Sanji said, pleased when Zoro finally met his eye again. "Is that the only question you know how to ask?"

"No!" Zoro shot back immediately, and Sanji grinned, glad to see that bit of spark return to him.

"How old are _you_ anyway?" he asked, snickering.

"Twenty…" Zoro paused to think of the correct word, but eventually finished, "Four."

Immediately, Sanji's nose wrinkled.

Great. They were the same age.

But wait, how did he know? It was near impossible to properly determine the age of a live shark, after all.

"When's your birthday?" he tried next, because on the off chance Zoro knew, he wanted fucking confirmation that he was older than the idiot.

Zoro just shrugged though, forcing Sanji to add, "Right. You're a fish. Why would you know your birthday. Gonna have to cut you up and get a look at your vertebrae to-"

But Zoro shifted then, closer to Sanji, and tapped a finger against the three red tattooed bands around his right bicep, two thicker than the third.

He pointed to the first and said, "Ten," then the second, of equal width. "Twenty."

The third was thinner than the first two, and when Sanji looked closer, he could see six tiny notch marks lining down from the solid band, in a few different places around his arm.

"One year," Zoro said, holding up a finger that he then drew across his arm to indicate another line.

Sanji raised a brow, grasping Zoro's arm and studying it gently.

"You telling me you can tattoo underwater?"

"O.H.A.R.A.," Zoro replied, shaking his head, and his eyes were fixed on Sanji's when the blond lifted them in surprise.

"O.H.A.R.A. did this?" Sanji asked, admittedly rather shocked to see something so akin to a tag on a perfectly sentient being.

"Robin said shouldn't, but - I said fine," Zoro answered, grinning, and he bent his arm so he could flex the muscle rather vainly right there underneath Sanji's hand. "Looks - good."

That dumb grin was far too charming for his own good, so Sanji was quick to scowl and push the merman's arm away.

"Weirdo," he muttered, gaze drifting instead to the black beaded necklace that drooped around Zoro's neck.

He reached out with the intention of touching it.

"What about this then-?"

But Zoro unexpectedly reached up to clasp the beads himself, jerking away with a low, threatening hiss, quick enough to startle the blond back.

As soon as he'd done it though, he seemed to become aware of his instinctive overreaction, emotion flickering back into dark eyes that looked sheepishly away, his shoulders slumping.

"...For a friend…" he muttered in the shocked silence that followed, his hand slowly letting go of the beads.

Sanji stared at him, closing his jaw just as slowly and bringing his own hand back down to the deck.

"Okay…" he mumbled in reply, averting eye contact and trying not to sound _offended_ when he'd seen the almost wounded look in Zoro's eyes for a moment there.

Touchy subject obviously. He wouldn't push.

His gaze drifted to the three golden earrings dangling from Zoro's left ear, but he decided not to bring those up for fear of a similar response.

Zoro had sunk down in the water somewhat, completely quiet now, and it was enough to make the situation awkward. Anywhere else with any _one_ else, the blond thought he would have left Zoro alone, but leaving him alone in the _sun_ made him nervous enough as is.

So Sanji sighed, slipped the bucket under the water again, and dumped its contents over the merman, hoping it would at least snap him out of the odd brooding.

It worked, Zoro's eyes sliding over to look at Sanji once more.

"So," Sanji said when he had the merman's attention. "Are all merpeople dicks like you, or are you just a unique case?"

Zoro's brow furrowed, a look Sanji was coming to recognize as one that meant Zoro understood nothing of what he'd said.

"...Dicks?" he repeated, and Sanji couldn't help but laugh. Loudly.

The next half hour or so was spent teaching Zoro various human curse words, which, in hindsight, was probably not a good idea, arming Zoro with such knowledge. But if the algae-head could understand exactly what he intended with his well-thought-out swears, then that was all the better.

Knowing just what being a shithead entailed was important…

It hadn't taken too long though to judge that the conversation was starting to exhaust the merman, most likely because of the language barrier, his already short replies becoming less and less, and his concentration clearly drifting.

Eventually, Sanji had sighed and reached out to pat the merman's shoulder.

"Go ahead and sleep or something," he said. "I'll make sure you don't dry out and shrivel up."

Zoro merely snorted, flicked some water in Sanji's face, then flipped back to his stomach so he could try and make himself comfortable again, arms folded over the deck.

Apparently it wasn't too uncomfortable though, and maybe Sanji felt a little twinge of accomplishment, because Zoro trusted him enough to pass out a minute later, eyes closed and mouth slack.

But he only felt accomplished for a minute, considering how damn creepy it was to see absolutely no movement, yet again, his gills not visible beneath the gentle froth of the water.

It was concern he really couldn't shake the longer he sat there staring at Zoro's peacefully still features, so he found himself reaching out to take hold of the merman's wrist gently, pressing fingers to his pulse point and waiting until he felt that slow and steady thrum.

He sighed, brushed knuckles against Zoro's cheek, then pulled his hand away, knowing he should really stop touching the guy while he slept….or in general.

Definitely in general. He couldn't afford to get wrapped up in something that was - well, obviously beyond him. At least not...in _that_ way….and dammit, the thought was there. It had entered his mind. How it would be to date a merman.

Fuck. No. Not going there.

Zoro wasn't the only one who probably needed a good dunk in some water…

* * *

It took them five hours and fifteen minutes to arrive at the O.H.A.R.A. facility, and the algae-head had slept for five hours and thirteen.

Sanji had stretched himself out on the deck beside the tank hatch, listening to the crackly Beatles tunes his dad had started playing from the boat's radio, eventually flopping a thin towel over his face to avoid getting burnt by the sun.

Every few minutes, he'd check on Zoro, but aside from that, the ride had passed smoothly and quietly, and he had to stop himself from dozing off a few times too.

In fact, he nearly had when Zeff finally slowed to signal their approach.

Sanji pushed himself up to his elbows, hissing when the hot deck nearly seared his skin, and he sat up the rest of the way instead, rubbing at them irritably before checking his watch.

Nearly noon now, and dammit, he was getting hungry. They'd packed some food to bring along, stuffing it in the small fridge in the cabin, but he hadn't eaten anything, and neither had Zoro, at least not since that morning.

But it was within a minute of the boat slowing down that Zoro's eyes suddenly shot open, as if sensing their approach, pupils dark and dilated until they shrank in the light dramatically, like the fucking shark he was.

The illusion was ruined a second later, however, when he let loose a loud yawn and stretched, smacking lips and scratching his chest like an old man.

"Welcome back. We're almost there," Sanji muttered, noting the coastline that rose up in tall cliffs, much different to the one near their center in East Blue, which was far more commercialized, roads only separated from the water by low concrete walls and fences in some places.

He remembered the approach to the O.H.A.R.A. facility by the time it came into view, the main center built on stilts over the water's shallows, in a rare break between the cliffs, with several outdoor enclosures worked into the very structure of the tide pools formed by said cliffs that rose above.

Several had staircases built into the sides of the rock, and there were a number of boats docked at the white platforms stemming from the main building.

It was far bigger and more impressive than their little B.A.R.A.T.I.E. and it seemed they had quite a few large guests residing in some of the rehabilitation enclosures, judging by the pair of huge black dorsal fins that poked over the water when their vessel came near one of the walls.

"Maybe….by boat isn't - bad-" Zoro said with another yawn, prompting Sanji to look back over at his sleep-bedraggled face. Why the bastard needed to yawn when he didn't use lungs was beyond him.

"Yeah, takes a fraction of the damn time if you sleep," Sanji muttered, and started to get to his feet to get a better look at their surroundings.

"Let me water here," Zoro said, pushing off the deck a little.

"Wait a sec-" Sanji started to say, already at the railing.

"I need - to go in other entrance - under," Zoro interrupted, and when Sanji didn't reply, busy leaning over the rail to watch their approach, the only warning he got was a growl behind him and then a splash.

He whipped his head back around, and Zoro was halfway to the platform at the stern, crawling his body over with strong arms and gritted teeth.

"Hey!" Sanji screeched, rushing over to him. "Don't just-!"

"Let him go, eggplant," Zeff's gruff voice cut in, the old man having opened one of the cabin windows so he was at least audible. "We'll meet him inside."

"What?" Sanji shot back, not understanding any of this, and hating how, yet again, his dad seemed to know everything that was going on.

Zoro had made it to the rope clipped over the step to the platform, and he was now flopped there fumbling with it stubbornly, growing frustration, and maybe a hint of desperation, on his face.

Sanji threw up hands, hissed a few curses under his breath, and stormed across to undo the clip with ease, throwing the rope aside and stepping onto the platform, hunkering down to shove arms under the merman.

"Come on, you idiot," he huffed under Zoro's weight, dragging him as best he could.

Zoro's arms came around him, surprisingly, though only to use the blond as leverage to push himself closer to the water, nearly taking the blond down with him in the process.

But Sanji managed to practically toss him in, clumsily, the merman flopping in sideways and disappearing into the white water the boat left in its wake.

His head popped up a second later, though already growing smaller as the boat continued on its way, and Sanji pointed in the direction of the facility to remind him where to go.

Zoro rolled his eyes, then arched his body and dove beneath the waves again, leaving Sanji kneeling there on the platform staring after him.

It was stupid, how much he _didn't_ want him to disappear, despite knowing he'd see him again only shortly….

He pushed down that dumb feeling and got to his feet.

* * *

What Sanji and Zeff were met with upon mooring their boat at the docks was, so far, pretty typical.

A grinning man in an open Hawaiian shirt, taller than perhaps anyone Sanji had ever seen, burly, with broad shoulders and chest, came to greet them, swinging over the rail of a nearby boat he'd been on to wave them into a free spot at the end of the pristine wooden dock.

"Bring 'er in slow. Little more…." he instructed, gesturing to Zeff with a large hand. "Alright, right there's good!"

Then he went right ahead and hopped aboard their boat to start securing it himself.

"Thanks, man," Sanji said, grabbing up the backpack he'd brought along with his laptop, in case he needed it, and striding over to where the man worked swiftly to tie the boat to the dock with a strong rope.

"No problem!" the stranger replied, looking up with a grin, affording Sanji a good view of his shaved hair, the stubble of which was dyed a brilliant electric blue, a thick forearm, decorated with a large star tattoo, lifting to pull down his angular sunglasses.

His eyes widened upon getting a good look at the blond.

"Whoa, hey there, you must be Sanji!" the man said, grin widening even more as he jutted out a hand towards him. "Franky's the name! You seriously look just like your-"

 _"Ahem…"_

Franky looked up, trapping Sanji's smaller hand in his tight grasp when he saw Zeff coming up beside his son with arms crossed over his chest.

"Your dad!" Franky finished, squeezing Sanji's hand one last time before letting go and bringing his to the back of his head. "Dr. Red! How's it goin'! Been a while!"

Zeff merely grunted in reply, leaving Franky to stand there awkwardly with a sheepish laugh.

"Aaaanyway," he finally managed, clapping a hand onto Sanji's shoulder and steering him towards the dock. "I'll show ya inside. Take it you're here to see the wife? Where'd Zoro-bro go? You let him off already?"

"Uh - yeah," Sanji replied, taking an extra moment to process being jovially manhandled by a guy he'd just met, but he soon relaxed, following Franky off the boat and onto the dock, his dad close behind. "He basically crawled his way off himself…. And wait. Dr. Nico's your wife?"

"Eh, not yet," Franky admitted, leaning in close a second later to whisper conspiratorially. _"But I'm workin' on it~"_

Sanji chuckled at that, deciding he liked this guy.

"If you need me to refuel ya before you head back later, let me know," Franky added as they approached the dock's intersection with a walkway that wrapped around the main building. "I'm the boat guy around here. Well….boats and-everything else. Water filters, enclosure maintenance. Anything ya need, I got yer back."

"Damn. We could use a guy like you around B.A.R.A.T.I.E.," Sanji mused, enjoying the disgruntled noise made by his father, who often did such work himself, along with Patty.

"Oh, but hey, Patty still work with you guys?" Franky asked, as if reading his mind. "We went to tech school together! Ask him if he remembers me, huh? You should've seen the mullet he had back then! Mine wasn't much better though~"

Sanji laughed.

"He does. And I've seen pictures! Me and another of our guys bought him a wig for Halloween a few years back," he replied, quite happy to listen to Franky prattle on about his school days as they entered the building through a clear pair of swinging doors that opened on a large lobby.

The differences from B.A.R.A.T.I.E.'s center continued, as this place seemed much more oriented towards the public, with various posters and TVs set up along the walls, playing educational videos full of scenes of ocean life.

The front doors on the opposite end were wide open, bringing in a fresh breeze and illuminating the place with natural light falling along the blue tiled floor.

Other glass-paneled doors were spaced evenly around the room, each labeled with fun little signs that indicated where they led, illustrated with cute sea creatures hanging off the letters.

They reminded Sanji of the illustrations Luffy's college roommate, Usopp, had done for a brochure of theirs two summers ago.

A giant fish tank curved in a circle in the center of the room, that also creatively served as a front desk, a woman standing behind it, leaning over a computer screen, her long orange ponytail falling over her shoulder.

"This is awesome," Sanji said, taking in the scene. "You guys open to the public?"

"Not today, but we run tours on weekends~ Sometimes field trips. The kids are fun~ Always ask the weirdest questions~" Franky replied as they neared the desk, the woman behind it having yet to look up. "Yo, Nami. Look who showed up~"

Finally, the woman turned her head to glance over at their guests, and while she looked disinterested at first, her eyes widened and she quickly straightened a second later.

"Well, would you look at that," she said, and stuck a hand out to Sanji just as forwardly as Franky had. "Nice to meet you, Mr. Red~ I'm Nami."

Sanji took her hand and shook it, a little taken aback by just how damn gorgeous this woman was, now that he could see her face, a bright, but slightly mischievous smile on her lips, and a spray of freckles over her cheeks.

"Sanji," the blond replied, left a little breathless when her nose crinkled adorably with her broadening grin. "Kinda...surprised everyone seems to know me here?"

Nami shrugged.

"Everyone knows your dad," she offered smoothly by way of explanation, then turned a smirk to Zeff. "Nice to meet you, old man~"

Sanji almost gaped at her, not because of her insolence towards his father - he couldn't care less about that - but because of how _attractive_ said insolence was. Shit. Just when he'd begun to believe he was off women for good…

Again, Zeff gave no reaction other than an irritated grunt before he turned to Franky.

"Dr. Nico's office, please?" he insisted more than asked, gaze drifting around the lobby as if he was about to look for it himself.

"Ah, no way she's in her office. Let's go down to the grotto," Franky replied, glancing at Nami. "You comin' with, girlie?"

"Maybe later," she said, and Sanji was surprised to feel a slight disappointment at that. "If Brook's down there, send him up. I wanna go over some of these migration patterns with him. After the last typhoon, the humpbacks have been moving like crazy!"

"Gotcha," Franky said, then jerked his head towards a doorway with a 'Marine Mammals' sign over it.

Sanji smiled, about to say a friendly, "Nice meeting you," to the woman, when she stopped him, slender fingers landing gently on his arm.

"Oh, and tell Zoro he owes me twenty pearls. He bet me he wasn't going to get lost again."

Sanji burst out a rather mean laugh, glad to find he wasn't the only one who recognized Zoro's idiocy.

"Gladly," he assured, then, with a wave, followed after Franky and his dad through the door.

Franky held it open for him, letting it swing shut once he and Zeff were through, but as soon as it did, he threw out a hand, stopping Sanji from going any farther.

"Hold up, bro. You're a first-timer, so gonna have to run a few things by you. Usually that would involve a lot of paperwork and signed legal shit, but - with yer dad an' all, think a quick run-down's all we need."

Sanji paused, eyes narrowing for a moment as another surge of irritation towards his father built within him. It was obvious. His dad knew everything. His dad had _been here,_ whatever being here entailed. _Fuck_.

But now was not the time to act sulky, even when his dad excused himself and headed off down the long white hall ahead of them, to wait for an elevator at the end.

Sanji stared after him for a second, only to be startled a bit when Franky's hand came down on his shoulder again.

"Kinda - feels weird to be tellin' you all this, but - you've never been here before so - gotta do it," Franky said with a chuckle. "Basically, long disclaimer short, all this is top-secret. Anything you see past here can't get out. Least not anytime soon. That means no tellin' the M.A.R.I.N.E.S., no tellin' the government, no tellin' yer girlfriend, and I'd say no tellin' yer parents, but - guess you're in the clear with that one. There's just - way too much that needs to be protected right now…"

The blond's expression hardened, listening to Franky's words and the seriousness that had come over his demeanor.

There was a lot to this, he could tell. There was more at stake than simply busting a myth. And there would surely be consequences, negative ones, as he'd suspected… Maybe he shouldn't have been so angry with his dad, if he'd been sworn to secrecy like this.

"I promise," he assured, dead serious. "Everything is safe with me."

He heard the sound of the elevator opening and closing behind him in the silence that followed, Franky judging him for a long moment.

But it wasn't long before the larger man broke into a relaxed smile once more.

"Thanks, bro~" he said. "Knew we could trust you~ Now, come on! Think you're gonna like what you see~"

* * *

Of course, the sights that awaited Sanji, after traveling down the elevator with Franky, to a basement-level floor that hadn't even been accessible without punching a special password in a small keypad, could hardly have been expected.

Gone was the cheerful, sunny atmosphere of the upper floor, replaced instead with a fluorescently-lit metal hallway that was empty when the elevator doors opened, save for a heavy-looking door at the end, a circular wheel handle in the center that seemed like an entrance to a bank vault.

Franky strode up to it confidently though, flipped open a keypad on the wall next to the door, and punched in a few more numbers.

A little red light flashed three times at the top, and he waited until it finished to press in another series. The light flashed again. He waited. Then more numbers.

The light flashed for a final three times, and Sanji thought that was it, but Franky made a little gesture with a finger and mumbled, "Three…..Two….One…."

Then, "Smile!" and he quickly made a weird pose with his arms over his head as a different flash, that of some sort of camera, blinded them out of nowhere.

"What the hell?" Sanji couldn't help but grumble out in his surprise, watching as Franky pressed one last key on the number pad, held it down for a few seconds, then released it to a heavy whirring click in the door.

Sanji found himself wondering just how the hell his father had managed to get down here on his own, considering he was no longer anywhere in sight.

A wink, and then Franky clamped strong hands down onto the door's wheel, which he began turning with vigor.

He was met with resistance first, but as muscles strained, the turning got easier, and Sanji's anticipation grew, building within his chest, a strange fluttering.

What would he find behind this door? A beautiful lagoon? Gorgeous mermaids sitting on rocks, combing their long hair and singing sweetly a siren's song? Would there be mermen of Zoro's physique? Strong and ferocious, sparring in the water with tridents crackling with magical power?

Whatever awaited him, he knew he had to calm himself, keep himself from passing out with the shock or excitement of discovering a whole new world he'd never known existe-

The door opened onto another bare hallway.

"Hang on, bro, one last punch-in~" Franky was saying, whistling a tune as he strode up to an identical-looking door at the far end.

Sanji scoffed loudly, even though he'd just met this man.

"Uh, you kinda built that up a whole lot," he muttered, shoving hands in pockets and stalking up behind him. "You could've said something before you….just….."

The door swung open, this time on its own, and _this time,_ the shock hit hard.

Because what it opened onto was a huge cave, albeit a well-lit one, the likes of which Sanji never could have expected, even within the towering cliffs he'd seen on their approach.

Stalactites hung from the ceiling, several stories above, and the water that lapped onto the smoothed-down stone floor from the veritable assortment of tidepools that stretched out before them seemed to be glowing, casting rippling blue light over the entire space.

"Don't worry 'bout the tide comin' in," Franky was saying somewhere to his left. "We got a whole filtration thing goin' to keep things dry~ Got some expensive shit in here, y'know?"

But Sanji was hardly paying attention to the lab benches along the walls, fully equipped with computers, nor to what looked to be a small _library_ , shelves and chairs nestled right on top of a naturally-formed platform of rock, alcoved in the wall of the cave.

No, it was the grotto's inhabitants, all of whom seemed to turn and look at him all at once as he stepped through the doorway.

There were merpeople alright, and while the place wasn't _teeming_ with them, Sanji counted two on first glance, and that was two more than he'd ever assumed existed a day ago.

Two mermen, both leaning elbows back on the floor casually as they sat in the shallows of the lagoon, tails flicking up water absently, turned to look at him, one, with dark hair and a strange tattoo on his cheek, pulling down a pair of _sunglasses_ , much as Franky had, to gape at him.

The other, with a shaved head and a red bandana tied over his forehead, seemed to react more dramatically, eyes visibly widening, his body quickly flipping around with a splash until he was barely poking his head out.

It was no matter, because Sanji was reacting much the same, eyes glued to those brilliant silver tails of theirs and his heart feeling like it would beat out of his chest.

The merman with the shaved head had averted eyes, ducking his head, and almost started to stammer something before the other gave him a hard whack on the shoulder and muttered something in his ear, in the same foreign language Zoro had spoken over the phone.

Sanji couldn't take his eyes off them, tuning out everything save for his fascination, until a slight commotion interrupted, and he was forced to wrench his gaze up across the pool to where, with a catch of breath, he realized a mermaid was sitting, wearing a black crop top with a skull design. Her thick pink hair was tied up in long pigtails on either side of her head, the drying curls bouncing down her back in ringlets.

And she was busy yelling at Zoro, floating beside her on his back, having paid Sanji and Franky's entrance no mind.

Sanji couldn't understand her, but Zoro clearly could, and yet he seemed to give zero fucks about whatever she was yelling, crossing both arms back behind his head.

There was a shorter man - a human man - wearing pink wetsuit shorts, with a curly mop of brown hair, standing in the waist-deep water beside him, poking and prodding at the wound across his chest.

This was the scene Sanji laid eyes on, but only for a moment before Zoro's locked with his.

Those eyes lit up, and he turned over in the water with a splash, ignoring the protests of the mermaid and the man's yelp of, "Hey! Zoro!" in favor of swimming over to the side of the pool closest to the blond, a smirk on his face.

"Question!" he proclaimed proudly, and reached up to gesture him over, shooting a smug look at the other two mermen, who continued to look on in shock.

Sanji had no choice but to stumble his way over, trying not to outright stare at the new merpeople as he neared the edge of the water.

When he was within reach, however, Zoro pushed himself up to grab Sanji's wrist and yank him down forcefully until the blond was down on one knee before him.

He turned his head and said something in his language to the other two mermen, who must have been his friends because, when they looked at each other with apprehension, Zoro rolled his eyes and repeated the same phrase until they tentatively swam over.

Then he jammed a finger right onto Sanji's eyebrow, _hard_ , and chirped, "Question!" again.

 _"Zoro!"_ he distinctly heard the dark-haired merman say before he lapsed into what sounded like scolding, and before Sanji knew it, the two were lost in a full-blown argument, none of which made any sense to Sanji.

Zoro still had yet to take his finger from Sanji's face too, and it was enough to snap him from his shock, the blond reaching up to finally shove the algae-head's finger away.

"Quit _calling_ me that!" he growled, glaring at Zoro, who merely looked smug again and turned to mutter something else to his friends.

"Oh my, he's taken quite a liking to you~"

A voice to Sanji's right, one he recognized from the phone, and he turned to see both his father and a tall woman with jet black hair heading towards him from the library area, descending the stairs carved into the rock until they reached the lower level.

Franky had, at some point, made it over there to meet them, and he offered a hand to the woman just before she reached the bottom step, which she took gracefully with a coy smile, blue eyes sparkling.

"Dr. Nico?" Sanji guessed, quickly getting to his feet and planting a foot into Zoro's head to shove him back down into the water nonchalantly.

"Yes," she replied, letting go of Franky's hand as she walked closer. "But please. Call me Robin. It's a pleasure to meet you in person again~"

"Likewise," Sanji replied, stunned by Robin's beauty as well, though he didn't notice nearly as much when his eyes kept wanting to wander back to the _merpeople_ currently floating in the water by his feet.

"Would you like a drink? Tea? Coffee? You must be hungry. Perhaps lunch would be a good-"

A scuffle in the water interrupted her, brought about by the curly-haired man, who'd succeeded in tackling an unsuspecting Zoro, though it only got him dunked in retaliation a second later.

Coughing and spluttering, the man resurfaced, but after a quick manipulative wibble of his bottom lip, Zoro had flipped over obediently with a groan to let him examine the healing wound again.

"Sorry, Robin," the man - who really looked no older than a high schooler - apologized. "But he wouldn't let me get a good look at it!"

"It's alright, Chopper," Robin chuckled, then turned back to her guest. "Sanji, this is Dr. Tony~ He hasn't received his veterinary degree yet, but his work as an intern has proven to be leagues above the rest, so do forgive me if I use a technically inaccurate title~"

Chopper's brown eyes widened….and then a bright red blush burst over his tan skin. He let go of Zoro and gave a gleeful little wiggle dance in the water.

"You idiot - saying that won't make me happy~" he practically squealed, a high-pitched giggle leaving him.

It was fucking adorable enough that Sanji grinned and replied, "Nice to meet you - Dr. Tony," which only served to make him smack Zoro hard in his elation.

Sanji half expected another squabble to break out, but it seemed Zoro was quite keen on accepting all of Chopper's abuse, something that...was a little endearing, Sanji could admit, particularly when he looked sheepishly away to avoid meeting Sanji's eye.

"Perona, if you'd be so kind as to join us too," Robin called, prompting the pink - haired mermaid - still watching the group warily from a distance - to slowly slide off her perch into deeper water so she could swim closer.

She didn't have a tail, Sanji realized, with some degree of surprise. Instead, she had a thin, almost transparent membrane that Sanji could see ballooned out from her waist like a skirt, several long tentacles propelling her along in the water as she moved.

"This is Perona," Robin introduced, though Sanji was still fixated on the saturated pink and purple dots that peppered her lower body. "She's quite unique. Her species is-"

"A mauve stinger jellyfish!" Sanji exclaimed, crouching down to try and get a closer look. "That's incredible!"

Perona made an indignant noise when he unconsciously reached a hand out, darting back in the water to escape his grasp.

"Damn right I'm unique!" she huffed, crossing arms over her chest. "So no touching!"

"Ah - my apologies!" Sanji stammered hastily. "I've just never-"

But something gave him pause….

"Hold on! That was perfect! Your accent - you don't have one-!"

"Well, duh!" she replied. "I've been learning your language since I was little! Zoro's the only one who doesn't practice like he should!"

Sanji gave a derisive laugh, turning a mocking grin to the algae-head, who was busy glaring at the girl.

"You idiot!" Sanji scoffed, then looked to the other two mermen. "So are you guys fluent too?"

The mermen jumped a little, as if Sanji addressing them was startling for some reason, despite their clear comfort with humans.

They shared a glance, and then the one with the shaved head piped up.

"Y-Yeah, but I mean - it's not such a big-"

He cleared his throat a little nervously, cutting himself off, then quickly ducked into a bow, instead of reaching out his hand.

"I'm Yosaku," he said. "It's an honor to meet you, sir."

"Johnny," the dark-haired merman added, with a bow of his own. "If you have any questions for us, we'd be happy to answer them. We're also sorry if Zoro-bro gave you any bad impressions of us merfolk. He's just been jealous and grumpy ever since the day he found out me an' Yosaku are called _'sword_ fish' in your language."

This was followed by a delayed, offended "Hey!" from Zoro, who'd taken a few moments to process what Johnny had just said, something that made Sanji smirk at the continual teasing. It seemed everyone here enjoyed taking the piss out of the dumb shark-man.

"Yes, well, I'll prepare some drinks, and we can sit down and have a chat~" Robin cut in, already striding past towards a door in the rock wall. "Is coffee alright?"

Zeff nodded his approval, as did Sanji, getting to his feet once more.

"Would you like any help?" he asked, but Franky beat him to it, following after Robin and shooting Sanji another wink.

"Got it covered, bro," he assured. "You're the guest~ We'll be right back."

The two crossed the cavern and disappeared through the door into a small kitchen, built with normal walls, painted a light blue and warmly lit, an interesting, homey contrast to the cool mystery of the grotto outside.

"You really think _coffee's_ adequate?" Franky asked once they were out of earshot, leaning in close to his girlfriend's ear as she opened a cabinet to pull out some ceramic cups and saucers.

She smirked, nudging him towards the nearby fridge where his favorite cola was stocked.

"Well, I'm afraid we're running low on truffles and _caviar~"_ Robin replied.

Franky just snickered.

"For the best. Doesn't go with cola anyway~"


	4. The Bracelet

Sitting in a beach chair at the edge of the water with a cup of coffee, munching on a stylish wheat bread prosciutto sandwich and enjoying the company of a beautiful, intelligent older woman who seemed to hang on his every word, Sanji was practically living out every high school fantasy he'd had, lying awake at night, trying to pretend he was one-hundred percent straight.

Of course, this was still an entirely unbelievable scenario for him, but that was because the beach chair was situated next to the glowing blue water of a cavernous grotto, and there were four _merpeople_ lounging about in the shallows. Dr. Tony had run off to prepare some antiseptic for Zoro, so that left four humans to balance out the merfolk.

Sanji sipped at his coffee as casually as he could manage, given the situation.

"It's hard to believe this is your first time seeing our facilities," Robin mused to him. "I'm sorry it had to be under such surprising circumstances."

"His fault," Sanji replied, hitching a thumb over his right shoulder towards the water where Zoro floated with arms propped against the smooth rocks.

In return, he received an irritated splash from the merman, who tried his best to get salt water in Sanji's drink. It didn't work.

"Indeed," Robin chuckled, smiling when Zoro shot her a grumpy look in return. "I'm mulling over the best way to go about this. Would you rather ask any questions you may have? Or shall I start detailing the history of our organization?"

Judging by the disgruntled noise from the water, and the bored look on Zoro's face when he plopped his chin into a hand rather dramatically, Sanji wondered if, despite how fascinating it would be to listen to Dr. Nico's account, the explanation might get a bit….lengthy. And aside from the scientific findings, the rest was pretty self-explanatory.

A research center secretly protecting and exchanging education with merpeople? As crazy as it sounded, it actually made a whole lot of sense, given what he knew about O.H.A.R.A.'s independence.

"Well," Sanji started, his head spinning a bit as he tried to work out one clear question in his head. "I guess, my first question is, how long has this whole...arrangement...been a thing? And how long has my _dad_ known about it? You said on the phone you've been working with Zoro since he was ten?"

Robin shared a glance with Zeff, Sanji noticed, though no words were exchanged, and his father remained quiet.

"As you know," she eventually said, her long index finger trailing over the porcelain of her coffee cup absently. "The M.A.R.I.N.E.S. was established by the World Government over ninety years ago, to initially provide research to aid the world war efforts, particularly for early submarine development. O.H.A.R.A. was created in response one year later, to study and protect the habitats and marine life that were affected.

"And in fact, it was O.H.A.R.A., based in West Blue as it still is now, that came into contact with the first merpeople, driven from their homes by the dangerous weapons testing occurring in the other seas. The M.A.R.I.N.E.S., at this point, was working closely with the Navy to do so. The first researchers of O.H.A.R.A. decided to protect the merpeople and give them insight into the humans' actions. This was difficult, at first, with the language barrier, mind. But it seemed merpeople had been observing what they could of the human world far before humans were even aware of their existence beyond legend."

Sanji couldn't help but turn eyes down to Zoro when he caught his movement out of the corner of his eye, the merman slumping shoulders and shooting Sanji a deadpan look, as if to say, 'I told you so.'

Sanji just reached out and flicked Zoro's forehead, contrarily quite fascinated by Robin's little history lesson because, unlike some idiot fish, he could _understand_ it. And it was real history that he'd never heard before, at least not with the merfolk added to the mix.

"After the war," Robin continued. "The M.A.R.I.N.E.S. had made their stance on marine life preservation quite clear, and this was what drove O.H.A.R.A. to break off as a separate faction, keeping the secret of the merpeople with them."

Again, Robin looked to Zeff, who'd crossed arms over his chest and leaned back in his chair, one ankle propped on his knee.

"As for when your father found out, perhaps this is a question best answered by him."

A few grumbling noises from the old man.

"I was thirty-five," Zeff answered gruffly. "Out here helpin' transport some pilot whales that had beached and needed care. Far too careless mermaid popped up to say hello while we were out on the water. She was just lucky I was the only outsider aboard."

This was all he said, and though this raised a million more questions in Sanji's mind - among them, who was she? Where was she now? - it seemed Zeff wasn't about to elaborate, and he caught the look Franky and Robin exchanged.

Was that disappointment…?

"Yes, well, we are very grateful for Dr. Red's involvement in our cause in the years since. Having him as an East Blue ally has helped sustain the populations that have migrated there," Robin said. "And we cannot thank him enough for the protective efforts he put forth during both of the government's seizings…."

"Seizings…?" Sanji asked, not liking the sound of that, particularly when he noticed the uncomfortable shifting of the merpeople, Johnny, Yosaku, and Perona all averting eyes. Even Zoro only met Sanji's eye briefly when he tried to look at him again.

Robin gazed, a little sadly, at the merfolk, but didn't shy away from the truth.

"Yes," she began. "Nearly twenty-five years ago, the Navy began to run more weapons tests in the waters around East Blue, with the M.A.R.I.N.E.S.' approval. The leader of the merfolk, at the time, was rather brash. He went against our advice and showed himself to the M.A.R.I.N.E.S. in a foolish attempt to negotiate and protect their waters. He'd become a scientist himself, after a lifetime of interaction with O.H.A.R.A., and he believed he'd developed the perfect negotiating tool.

"This wasn't the case, as, ultimately, his actions - and the harrowing interest of the M.A.R.I.N.E.S. over the merpeople's reveal - led to the capture of several merfolk for study, including, very regrettably, some infants. And their leader was killed in the fight that ensued."

Sanji's stomach dropped.

Merpeople? _Children?_ _Captured_ for study? Held in _captivity?_

Suddenly, he felt _very_ sick, trembling hands lowering his coffee to his lap, his chest tight and his head doing a nauseating spin.

"Wh - _What?"_ he breathed in disbelief, hoping to _fuck_ there was some twist to Robin's words.

There wasn't. He could tell by the heavy air that had fallen over the cavern, the way his father's, and even jovial Franky's moods had dropped, the blue-haired man leaning forward with elbows on his chair's armrests, fingers steepled together as he stared gravely at the floor.

Robin nodded sadly, but her blue eyes were clear, watching Sanji as she spoke.

"Afterwards, our efforts doubled to protect the merfolk, who hid themselves far more thoroughly. The M.A.R.I.N.E.S. pursued them, however, and though it took another ten years for them to finally locate the East Blue colony, I'm afraid they acted again."

Her gaze shifted to Zoro, and Sanji's heart thumped painfully in his chest because, suddenly, he wondered, with dread...

"Zoro himself was nearly taken," Robin murmured gently. "Thankfully, they haven't attacked since. But of course, the effects are lasting…"

Sanji's eyes closed, a shuddering breath leaving him before he turned his head slowly to look at the merman, whose gaze was, a little surprisingly, already fixed on him silently. Sanji's eyes drifted down to the black beads hanging from Zoro's neck.

Zoro stared back solidly, even when Sanji's shoulders slumped and his mouth opened wordlessly, giving a tiny shake of his head.

What was there to say? Absolutely nothing, and, as a human, especially one working in East Blue, he couldn't help but feel incredibly pained over all this. Pained and _guilty_ , even if there was nothing he could have possibly done to help.

" _I - I'm sorry…"_ was all he said after a long moment, eyes still fixed on Zoro.

All other questions he had, about the merfolk, about O.H.A.R.A….all of it left him, and he wasn't sure why. There was so much he was curious about, but it hardly seemed the place to be inquisitive, when it was clear the merpeople had a far darker history than he'd first assumed.

"It's not gonna happen again," he heard himself saying, in the silence that followed, and he wasn't saying it to Robin. He was saying it to the four in the water. To Johnny, Yosaku, and Perona. To Zoro, who'd lifted a brow at the commanding tone to Sanji's voice.

"It's not," he repeated decisively, this time turning back towards the humans. "We can't let it. Even if it means B.A.R.A.T.I.E. stakes jurisdiction over North Blue and South Blue too."

"Eggplant, it's not that simple," rumbled his dad, but Sanji was adamant.

"Right, because a damn _human rights_ violation is up for debate-" Then he huffed a breath and amended, "Whatever. _Merpeople_ rights. But it shouldn't matter! We protect every species, and it's obvious they're more than just a _species._ "

Zeff made a grumbling noise, and he seemed likely to say something else, but Robin's chuckle interrupted.

"Remind me why you didn't tell him sooner?" she asked the older man, a teasing glint in her eye.

"My thoughts _exactly!"_ Sanji yelped indignantly.

Robin smiled, sharing a glance with Franky, who wiggled eyebrows enticingly.

"I have to assume you're curious about their biology as well. Dr. Brook is out tending to the whales, but he knows a great deal about their culture. You may ask him anything you wish. Or myself and Franky, of course. And naturally, any of our friends here."

She gestured to the merpeople.

"Nothing personal though!" Perona piped up, arms crossed over her chest and a pretty pout on her lips. "I don't know you!"

Robin chuckled again.

"Perhaps you'd prefer perusing our library instead," she offered, extending a hand towards the cozy alcove nestled on a higher level of the cavern.

"You brought yer laptop or somethin'? I can get you set up for access to our online database too," Franky added, jerking his head towards the backpack Sanji had by his feet. "Just gotta make sure your computer's protected. Don't want any leaks."

"Wow, really?" Sanji asked, surprised. "Uh - yeah! Please. Damn."

Would any of this ever sink in…?

...

Probably not, because some ten minutes later, sitting on the ground by the water, with Franky seated across from him, typing away on Sanji's laptop after having stuck some kind of thumb drive into the USB port, the blond still found himself craning his head up at the towering cavern ceiling in amazement.

Robin had taken the various cups and dishes back to the kitchen, and Zeff had moseyed off towards the library, but Sanji didn't much care what he was up to, because Johnny and Yosaku were excitedly detailing an underwater cave near their current settlement that had all kinds of ancient artwork from their people.

"Yeah, and there were all these weird arrows leading deeper into the cave - it was creepy!" Yosaku explained, talking quickly in his excitement. "So we sent Zoro to check it out while we waited at the entrance - you never know what kind of things live in those caves! We waited for like an hour-!"

"I think it was two hours," Johnny cut in.

"Alright, two hours-" Yosaku corrected. "But he never came back! We thought he got eaten! So we were all ready to go back and tell the Queen that she lost her best warrior, but then the freaking rocks in the wall started dislodging themselves-"

"And it was Zoro shoving his way out like a damn crab!" Johnny finished, both him and Yosaku cracking up together at the stupid memory.

"Right, Zoro?" Yosaku stuttered out between laughs, thumping the back of a hand to Zoro's chest. "We never figured out _how_ the hell you got in there."

Then he kept right on laughing, and Sanji realized with glee, judging by the entirely baffled look on Zoro's face, that the dumb merman hadn't understood a word of what his friends said.

The annoyed fake laugh he gave in response to his friends cackling in his face was enough to confirm that.

As amusing as Zoro's complete lack of comprehension was, there was still something Yosaku had said that left Sanji rather baffled.

"Wait-" he interrupted, still grinning. "You have a _queen?"_

This question was accompanied by all sorts of fantastical images bursting through his imagination. A beautiful, majestic mermaid - maybe with magical powers - sitting regally on a throne of colorful coral, a trident in her hand, hypnotic eyes boring into his soul….

Was that too over the top?

He wondered if it might be, judging by the slow, almost curious looks the merpeople exchanged, and he caught the eye roll of the seemingly disinterested Perona, sitting apart from the group again as she fiddled with her hair.

"Yeah…" Yosaku replied slowly, though Sanji's eyes had drifted to Zoro, who'd quirked a brow right back at him, barely suppressing a smirk. What was that about…?

"There's a few different kingdoms around the world actually," Yosaku continued. "But, our kings and queens are….a lot more informal, I guess you could say. None of this fancy ceremony and stuff like yours. They're more like - chiefs….leaders. Y'know, that kind of thing-"

"We have a palace though…" Johnny mumbled, cutting in.

"Okay, but - it's not exactly the same."

Too late though.

"A _palace?"_ Sanji nearly yelped in disbelief. "Are you fucking-? For real? Like underwater Atlantis shit?"

He whipped his head back to Franky, still typing away on his laptop.

"Please tell me you have pictures!"

Franky merely chuckled, pausing his work to chug back some cola from the bottle that sat on the ground beside him.

"Nada, bro. Not of the palace at least," he replied. "Queen doesn't want the location gettin' out. She hasn't been up here in a few months. But she's pretty strict on what she wants shared these days."

Sanji couldn't help it. He groaned loudly at that missed opportunity, even as Franky gave a few last clicks on his laptop.

A satisfied nod and the man passed it back to him, large hands practically dwarfing the thin device.

"Anyway, you're all set," Franky said. "Main password's 'undadasea'. No spaces. Spell it like they sing it~ You're gonna have to set a few more yourself though. Sorry, but we gotta track your computer now too. Just the location and any activity on the database. Also, I can take the whole thing offline at the click of a button, so just be real careful, okay?"

"Gotcha," Sanji said, eagerly taking the laptop off Franky and spending the next minute or so setting up a series of passwords when prompted.

But once he was in, he was _delighted_ to find an entire encyclopedia of searchable information.

It was so thorough that it was almost too good to be true. It seemed like it should have been fake, some elaborate publicity stunt for a movie about merpeople, and he definitely would have believed that if it hadn't been for the very real merfolk mere feet away.

"Holy _shit,_ " he breathed, clicking eagerly through to the known species of merpeople, "Who wrote all this?"

"A lot of it's transferred in from some books we had, written over the years by past members of O.H.A.R.A. Amendments and any articles from about fifteen years ago and up are approved or written by Robin," Franky explained proudly. "Though I got a few credits in there myself~ 'Bout their weapons an' tools an' stuff."

"Damn…" was all Sanji said again before he went quiet for a few minutes, save for various noises of shock and disbelief as he scoured the incredible resource, tearing into the information with fervor.

There was _so much_ , about the merpeople's diets, their physiology, complete with images of X-rays, how they compared to the normal fish of their species.

They were mammals, amazingly, most capable of live births, and some kinds, those fused with dolphins in particular, even had dual respiratory systems.

They were warm-blooded, but capable of withstanding temperatures far colder - pressures far greater - than any human could.

But for every question answered, it raised countless more that were yet unanswered. Next to nothing was known about their evolutionary process, how they had even come about, and Sanji began to realize it was because humans hadn't explored. Much of the merfolk's way of life, their structures and societal behaviors were left untouched, out of _fear_. Fear of exposing too much, of venturing too far and risking their exposure.

And it went both ways. The merfolk had advanced, intelligent civilization, with recorded history and language, but only a select few groups had chosen to interact with humans, and even then, they were secretive, defensive of their culture.

But so much was _missing,_ dammit….and selfishly, Sanji couldn't help but feel dismay over that, despite what he'd learned today of the strife between the humans and merfolk.

"Brat. Read it on the way back," came a gruff voice behind him, his father coming back down to their level from the library with two large weathered-looking books in hand. "We got a long trip an' daylight's disappearing."

" _What?_ Oh, come on!" Sanji whined instantly, as if he wasn't a full-grown adult but a kid having his time at an amusement park cut short.

Nevermind that he knew there was still work to be done back at B.A.R.A.T.I.E. But after everything he was discovering _here_ , he didn't want to leave.

"We still have to record all the samples we got yesterday," Zeff was rattling off. "And you've been putting off damage-checking the outdoor enclosure after that storm a few days ago-"

"Ugh, I know, I know…" Sanji muttered. He'd done a surface check though….and the tank was empty now. It wasn't even an urgent problem.

Still, excuses aside, he sighed, reluctantly snapping his laptop shut and stowing it in his backpack before taking Franky's hand, the man having stood and offered it down to him.

He got to his feet, hoisted the pack over his shoulder and gave a wistful glance around the space.

"No worries, bro," Franky said, squeezing his shoulder. "You're welcome back any time!"

"Quite right," Robin agreed, coming out of the kitchen and leaning a hip against the doorframe.

Sanji wasn't sure he'd ever seen anyone make a zip-up wetsuit top look as elegant as she managed to do, but that was beside the point…

"We'll walk you guys out."

Franky's hand left his shoulder as the man headed towards the heavy metal door that Sanji had first come through, Robin joining him.

But Sanji didn't move right away, lingering where he was by the water, slowly looking back down to where Zoro and the others bobbed.

"Brat, let's go," called Zeff.

"Would you give me one second, old man?" Sanji snapped over his shoulder, a little more nastily than intended, but Zeff merely sighed and walked off towards the door with Franky, and Robin, who hid a chuckle behind her hand.

Before long, they were all through, and the door had closed behind them, leaving Sanji in the cavern, the lone human.

It was only a second though before Johnny had elbowed Yosaku, jerked his head towards the water, then motioned for Perona to do so too.

The mermaid made a small indignant noise. Then, without so much as a farewell, slipped beneath the surface and swam off, mumbling to herself in her own language.

Johnny and Yosaku at least had the manners to say goodbye, if far more formally than necessary.

"Nice meeting you - S - Sanji," Yosaku stammered, face turning red as he bowed deeply, almost seeming to doubt his own words. "I hope - I mean, it would be nice if we could see each other again."

"Yeah," Johnny said, bowing as well. "Let's meet again."

"Likewise," Sanji replied, a little surprised they were leaving. "But you don't have to be going so-"

"It's okay, bro," Johnny assured. "We oughta be gettin' home anyway. We're all finished here. Just been waitin' to see if Zoro-bro was okay."

He turned his head to Zoro with that, muttered something in their language. Then, with another nod to Sanji, he and Yosaku sank beneath the surface too.

Neither Zoro nor Sanji said anything in the moment that followed, and in fact, Sanji simply sighed and lowered himself down to the ground to sit cross-legged before Zoro.

The grotto was quiet, save for the lapping of water echoing, the slight splash Zoro's tail made when his caudal fin flicked above the water now and again.

He tried not to let his eyes linger on Zoro's beads for too long.

"I meant it, y'know," he said softly after a minute. "I'm not gonna let them hurt you ever again. I dunno how, but I'm not letting it happen. I promise."

Zoro watched him with that same look of calm certainty he'd had before, and he eventually replied, "You won't," with equal certainty.

Despite the seriousness of the moment, Sanji felt himself smirking in the face of Zoro's confidence.

"So you trust me now?" he asked, and something inside him stirred when Zoro grinned back and nodded.

"'Bout time," said the blond.

Fuck.

He'd leaned closer unconsciously, elbows on his knees, and Zoro had done the same against the rock.

This was bad. Because the urge to move even closer was strong, and that was _fucking_ ridiculous.

Zoro was attractive. And the merman's lack of inhibitions only made him more so. Sanji could admit this now, without qualms or the insecurities of his younger self.

But unlike with Ace, or anyone else for that matter, Zoro wasn't _human._ And Sanji could _not_ afford to fall into this as easily as he had before, when there was a _lot_ that wouldn't work. A damn _lot._

Still, that left him with the fact that he very much didn't want to leave. Because who knew when he'd see this stupid mossball again…

Zoro didn't seem uncomfortable with the silence that had befallen them when Sanji lapsed into his internal thoughts.

By the time Sanji had become aware such a long pause had even occurred, Zoro's eyes had drifted, lingering on his lips, he was pretty sure. They'd certainly looked downward, in any case, and for a fleeting, indulgent moment, Sanji wondered if Zoro was thinking similar thoughts.

Were merpeople even attracted to humans? Had such a relationship ever existed…?

"Um…" Sanji stuttered when he realized the silence had stretched a touch too long. "Look, you know you're safe at B.A.R.A.T.I.E. So if your stupid wandering ass or - tail or whatever - flops up there, I mean…."

The look on Zoro's face as Sanji struggled to come up with the right words became positively gleeful, and he shifted closer so his forearms brushed Sanji's knees.

"You - _want_ me to…?" he trailed off, not having the human words to finish the sentence, but the effect was there, namely the bright flush that took over Sanji's face.

" _No!"_ he answered immediately, mortified when Zoro pressed closer and copied him with a, " _Yes!"_

"No!" Sanji screeched again, automatically getting right up in Zoro's face….a bad move when Zoro merely tried to bite his nose off with sharp teeth.

The blond shoved Zoro in disgust, quickly getting to his feet and gathering his things.

"You owe Nami twenty pearls!" he shot back in retaliation, smirking at the offended expression that assaulted Zoro's face.

"What?!" the merman shrieked, but Sanji was already backing away, well out of grabbing range.

"For getting lost~" he replied.

Then, before he could linger for too long, he slid backwards towards the door.

He stopped just in front of it, quirked a brow at the algae-head sulking in his direction from the water, looking incredibly frustrated by his lack of legs in that moment.

"See ya around, Zoro~" Sanji said as sweetly as he could manage beneath the pounding of his heart and the hope that this _wasn't_ the last time he'd see the merman.

He slipped through the door, wondering what would have happened if he'd kissed him.

* * *

Zoro had never particularly wanted to be human. He didn't find them particularly interesting. They had to worry about actively breathing and stuff - walking and gravity. They ate dumb shit, like lettuce, and they couldn't swim for shit either.

Aside from probably Franky, Zoro hadn't met any human who stood any chance of killing something with their bare hands or teeth, and the weirdest part was that humans didn't _want_ to. They lacked the same instincts when it came to survival, and they relied on cheap tools and shit to do all their fighting - and most of their work in general.

But watching Sanji disappear through that door, shoot one last fleeting glance over his shoulder before it closed...

Zoro had never wanted to sprout legs and run after him more than he did in that moment.

His tail flicked back and forth with agitation, and his body tingled, that feeling of familiar disappointment and yet unreleased energy twitching through him like it did on the rare occasions some lucky prey got away from him.

But Sanji wasn't prey. Sanji was - something else...and Zoro was honestly surprised to find these instinctual feelings of want and attachment could even apply to humans.

And to _that_ human in particular?

He was in trouble.

Zoro usually chose to close out the very human emotions that he was definitely capable of feeling. He let his shark half rule. He did as he pleased and actively tried _not_ to feel because he knew what that brought.

As it was, he'd nearly let himself be overcome today, when Robin had told the merpeople's history….when Sanji had nearly touched his beads on the boat ride over….

He hadn't _felt_ emotional like that in a long time.

And he also hadn't smiled, laughed, felt everything slip away as easily as it had when he messed with that weird blond. He hadn't connected emotionally with _anyone_ , merperson or human. Not like that….not for years...

It was a foreign feeling, the fluster that rose along with base instincts, the feeling of his heart fluttering in his chest, that excited clenching in his gut that made him want to run hands slowly and gently over Sanji's form, just as badly as he'd felt the urge to stake his claim - to shove him up against something and sink teeth into his skin to assert dominance.

He knew merpeople were capable of softer feelings like that. All of his friends let that part of themselves take precedence far more than he did...

Zoro gave a little growl, almost against the very idea, then turned and dove beneath the surface because he knew the longer he stared at that door, the more frustrated and confused he would become.

The pool deepened rather quickly, beyond the shallows, dropping off into the deep tunnels that led out of the cave system to the ocean beyond.

Normally, it would be dark, and though the merpeople's eyesight was even better underwater than it was on land, it helped that Franky had installed lights into the rock surfaces below, giving the water its unearthly blue glow. He'd even put up signs over the different passageways, indicating where each tunnel led so they could find their way out easily.

Zoro was some thirty feet beneath the surface, heading towards a left-hand tunnel that he knew would put him in the right direction to swim back to East Blue (despite the sign over it reading 'North'). He knew he needed to wait around for Chopper to get back, but in that moment, he needed some fresh water.

But, in a split second, a dark figure darted towards him in a flurry of bubbles, its shape silhouetted in the lights leading to the tunnels, and he had just enough time to brace himself when, with a ferocious sound, Johnny collided with him at top speed.

His teeth were out, and he seemed intent to ram Zoro into the rock wall, though immediately, Zoro's fighting instincts kicked in, pupils dilating and muscles contracting to shove the other merman back.

Johnny was relentless though, and his voice was low and fierce because of it, rumbling clear, even under the water.

" _What the hell were you thinking, Zoro?!"_ he growled in their language, just barely dodging a powerful hit from Zoro's tail before his hands clamped down on both of Zoro's drawn fists. _"You could've given us away! What if that fisherman had seen you?! What if he'd called the M.A.R.I.N.E.S.?! What if you'd_ _ **died**_ _!"_

 _"Shut up! I wouldn't have!"_ Zoro growled right back, pushing Johnny away again and nearly landing a punch to his jaw, had the merman not flipped away in time. " _The asshole was fishing right by the reef! And Chimney and her stupid catfish were messin' around there! The hell was I supposed to do?"_

" _Uh, I dunno, not attack a fucking_ _ **boat**_ _?"_ Johnny shouted, and he was about to rush Zoro again, until Yosaku swam up beside him, a tentative hand on his arm to hold him back.

The dark-haired merman stopped, but hissed his frustration.

" _If you'd ended up with anyone but Dr. Red, it would've been bad,"_ he eventually continued, barely succeeding at calming himself. " _Hell, we are_ _ **so**_ _damn lucky Sanji wasn't like the M.A.R.I.N.E.S. The Queen would be so-"_

" _Did you seriously fucking expect him to be like them?"_ Zoro bit out, though he did bring fists back down to his sides, no longer baring teeth as ferally. _"The only thing that gave me pause for a second was B.A.R.A.T.I.E., but it was obvious that the damn curly question was harmless-"_

" _Zoro-!"_ Yosaku interrupted, sounding a little fearful, his eyes flicking up to the surface as if Sanji would overhear them, despite having left. " _Quit being so disrespectful…"_

This only earned him a dramatic roll of eyes and a loud groan from Zoro.

" _Bro,"_ Johnny insisted. _"He said those things about helping us. And he seemed cool, yeah, but we only just met him! We shouldn't trust him so readily. We need to talk to the Queen. Tell her what happened and_ _ **then**_ _-"_

" _He should be the one to talk to her."_

Zoro's voice was level, as was his stare, level and entirely set on his decision.

Johnny and Yosaku shared a surprised glance.

" _What…?"_ Yosaku stammered.

 _"He could help us!"_ Zoro exclaimed. _"He already lives in East Blue! He wants to help us! And you_ _ **know**_ _Robin still has one of the-!"_

" _No -_ _ **No**_ _! Absolutely not!"_ Johnny protested, wrenching his arm from Yosaku's grasp to dart towards Zoro again. _"Bro, have you lost your mind?! He goes missing, don't you think they're gonna scour the oceans for him? He's a biologist and regardless of his morals, B.A.R.A.T.I.E.'s still part of the-!"_

" _He told me B.A.R.A.T.I.E.'s not part of them!"_ Zoro growled, blocking Johnny's advance by ramming his forearm assertively into the other merman's chest. " _M'not supposed to say anything, but he an' that Dr. Red guy are trying to break B.A.R.A.T.I.E. off, just like O.H.A.R.A. You talked to him! You seriously think he's gonna reveal us? We've actually got a shot at finally stopping the M.A.R.I.N.E.S.!"_

At that, Johnny's brow furrowed, as did Yosaku's, because they heard that tinge of desperation in Zoro's voice. Their friend hadn't given this up. For close to fifteen years, he'd been dead set on toppling the M.A.R.I.N.E.S., something that was, as far as they knew, a damn impossible goal given the circumstances.

He hadn't stopped wanting this….not since…

" _Zoro…"_ Johnny muttered, voice softer now than it had been. _"I know - I know…. Kuina was…."_

" _Then what's the problem?!"_ the other merman shot back, frustration and rare upset making its way into his tone.

 _"What is he going to do?"_ asked Johnny, growing exhausted with the argument. _"It doesn't matter who he is, in this case. Fact is, he's human. A human who doesn't know shit about us. It's not gonna amount to anything. We're better off protecting our own…"_

 _"And everything Robin and Franky and them have done for us over the years? Does that mean fucking nothing?"_

 _"No - of course not! Zoro, that's not what I-"_

Johnny stopped, closed his eyes and took a moment to clear his thoughts, slow the irritable pounding of his heart that was really more fearful than anything. This was all sounding too familiar….too similar to how things were all those years ago…

" _Can we please just….talk to the Queen?"_ he murmured after a minute. _"See what she says first before we do anything crazy?"_

Zoro was looking away steadily, arms crossing his chest, and it was clear in his eyes that he was somewhere else, remembering something else, things that Johnny and Yosaku had no hope of relating to, but they did hope that Zoro would listen now at least, even if he rarely did. Even if he hadn't back then.

But surprisingly, Zoro eventually replied, _"Fine,"_ though he didn't look over, and in fact he gave a flick of his tail, propelling himself up a bit towards the surface. _"You guys go ahead. I gotta stay and wait for Chopper."_

It wasn't a lie, of course. He really did have to wait for him to return with the medication he'd set out for, though it was also partially a request to be alone, something that wasn't too out of the ordinary, given his solitary nature.

His friends knew this, and, thankfully, respected this, evident when they both backed off without another word nor any jibes about Zoro getting lost on the way home.

Only Yosaku hesitated, pausing to look back at Zoro for just a moment before he swam after Johnny, who'd already gone deeper towards the East Blue tunnel.

Zoro waited until they were gone, then, with one beat of his tail, coasted back up to the surface where he flopped himself in the shallows again to wait, now completely alone in the grotto, for Chopper.

He wondered briefly if he should heed his friend's advice, if he should really be more cautious of Sanji.

But then he thought about the blond's enticing smirk, how serious he'd been when he'd promised he wouldn't let anything bad happen.

Yosaku had told him not to be disrespectful….but wouldn't it be _more_ of an insult to Sanji's name if he _didn't_ trust him?

Absolutely, he decided.

His mind was made up.

* * *

Chopper had returned, not long after, slathered some weird ointment all over his healing wound and tied a waterproof container to Zoro's wrist, with some pills he ordered Zoro to take for the next few days, to prevent infection or something.

The merman put up the obligatory fight, but would probably adhere to his instructions….if he remembered.

Robin had made him stay for the language lesson he'd missed, but he could tell it was in part to get him to rest before swimming home. Not that he needed it. He would've been fine. The trek, while it might be long for a human, was pretty standard for their species. Sometimes he could tell humans didn't really get that.

Franky had come back that evening, barbecued some shrimp for dinner, something that Zoro had actually developed quite a liking to, even if human food was often far too elaborate for his tastes.

Brook had joined them, the old man turning on some music on whatever the hell Spotify was, and Zoro had admittedly forgotten some of the tensions of earlier in favor of watching Brook, Franky, and Chopper get a little too tipsy off the weird beer drink that always made humans act like idiots. Every time he asked to try it, Chopper would vehemently refuse, insisting it would kill him.

Zoro highly doubted that.

He'd stuck around, mostly to prove all was well, and he _hadn't_ gone pearl-hunting for Nami, thank you very much, the woman having gone home early to prepare for a date with a girl or some shit. One of those strange mating rituals humans did.

He'd stayed until that evening, said goodbye to everyone and pretended to leave himself, when in reality, he'd waited around underwater until there was no movement in the cavern above him, until lights were turned off, and all that remained to illuminate the space was the ethereal glow of the water.

Only then, when even Robin, who often stayed late to read, had left, did he pop back up, eyes already on the door across the cavern, the unsuspecting door that looked just like the rest, yet was his goal to get inside.

Could he do it? He'd never tried such a thing before, but he'd have to, wouldn't he, and he was pretty sure he knew the right password to get in.

In no way was he _stealthy,_ but, with any luck, he could at least get the door open, crawl back for water, then make one last trip for what he _hoped_ would be easy to find inside.

Conviction on his features, he took in a conscious flow of water through his gills, let the oxygen invigorate him for a second.

And then he planted hands onto the rock surface and pushed up out of the water, fists clenched and forearms already working to pull himself across the flat ground, eyes on the door the entire time.

His tail dragged limply behind him, and the comparative roughness of the floor was a little painful against his skin, but he powered through with minimal discomfort, and managed to make it to the door quickly.

From there, he grabbed a rolling chair from the lab bench against the wall, shoved it towards the door, then heaved his torso up onto it as best he could in order to reach the keypad beside the door.

He stayed focused, flipping open the keypad's cover and typing in the four digits he knew he'd seen Franky program as the password.

0-2-0-6. Robin's birthday.

Sure enough, the LED light turned green. A clicking sound, and the door easily swung forward when he pushed down the metal door handle.

He slid off the chair, propping the door open with an arm, and shot a glance over his shoulder at the water beyond.

He felt okay. The air was wetter here, not like under the blazing heat of the sun outside, so the awful burning and the suffocating feeling of his gills closing up hadn't kicked in yet.

Maybe it was foolish, but he decided to push a little farther, to at least get a chair set up inside so he could reach the counters in what he knew was a small laboratory, but an important one.

He shouldered the door open the rest of the way and managed to crawl his way in, harsh fluorescent lights turning on, activated by the motion.

More lab benches lined the walls, and though he couldn't see what was on top of them from his low angle, he had to assume there were yet more computers, maybe microscopes or other ridiculous tools, most of which he still didn't know the use of.

Fuck. It was hard to see _anything_ , the room as unassuming and clinical as it was. He didn't know what he'd been expecting. More of Franky's handy directional lighting? Clear labels? Not that he'd be able to read most of them, but it would be a start.

He crawled forward, because the door clearly wanted to shut, and he wasn't going to stay wedged in it while it did.

Except now his body was growing heavy. His arms were strong, and he managed to get through, curving his tail out of the door's way, but it was with enough effort that when he heard the door click shut behind him, it instilled a tiny bit of panic.

Shit.

Change of plan.

He'd prop the door open with something, go back to the water, catch his breath, then come back and try again.

So he reached out and grabbed the nearest chair, shoving it, with a bit more urgency, at the door, the chair's wheels clattering loudly against the painted metal.

There was an uncomfortable tightening in his chest as he pushed himself up to the seat to reach the door handle, his heart having picked up speed, and he felt his torso contract in protest when he instinctively tried to open his gills to let in water.

Again, he almost panicked, arms fumbling a bit on the chair, but he gritted teeth and forced himself to remain calm as his hand closed around the handle, tugged down, and pulled.

But the door didn't open. The door stayed shut, and when he gave another hard tug, there was nothing, no give.

It was fucking locked, he realized with a feeling of dread, and when eyes darted to the small black box beside the door, he was rather horrified to find that it wasn't the familiar keypad he'd always seen Franky punch numbers into.

There _were_ no numbers. No buttons. Just a small red light glowing behind a tiny square of clear plastic positioned in the center of the little box.

He pressed fingers to it, shoving himself up higher on the chair, gripping the back for dear life as he jammed fingers against it over and over, yanked at the door handle frantically.

His gills twitched fruitlessly now, despite his best efforts to control it, but there was no denying that he was in some pretty deep shit, particularly when his arms slipped and he found himself sliding off the chair to land rather hard on the floor, crushing a pectoral fin painfully.

Stubbornly, against the burning of his gills and the terrible lightheadedness, he struggled to get up again, to force his arms to work, to do _something_ to get himself out of here, even though he didn't know what.

His tail began to thrash erratically though, making any productive movement near impossible now.

He was suffocating, and though the air was, in reality, quite cool, he felt nothing but heat searing through him, his heart thundering at alarming speed in his chest.

He wasn't going to make it, he realized far too late. And though his arms gave one last quivering effort to drag him forward, his vision was graying, and he vaguely registered uttering a choked swear before all went black.

* * *

"Some day, huh," Franky murmured, fingers threading gently with his girlfriend's as they stood, no one but the two of them, in the dark lobby, the soft light of the front desk's fish tank casting rippling shadows across the carpet.

"Some day indeed," Robin agreed quietly, taking the private moment to step closer and brush her nose against Franky's gently. "To be honest, I'm fairly surprised Dr. Red let him come~"

"Yeah," Franky chuckled in response. "And Zoro seemed pretty damn - uhh - _interested_ in him..."

He trailed off, but the suggestive wiggle of eyebrows and the way he bit his lip was enough to draw a smile onto Robin's face.

"Yes, that was perhaps the most curious thing of all~" she said, and leaned closer to steal a quick kiss to that ridiculous grin on Franky's lips.

"I'm glad," she added, a touch of melancholy in her voice. "I've been worried, admittedly. His human qualities have been fading quite prominently as of late…."

Franky's grin fell somewhat, his hands releasing hers, moving delicately to her hips instead.

He'd noticed it too, how distant the merman had become. How it would take him longer than normal for his eyes to regain their clarity, particularly after he fed.

"Not around Chopper-bro," Franky teased, trying to lighten the mood some, but Robin's lips only twitched up slightly.

"Not around Chopper, but….I've recently unearthed some troubling theories from Dr. Clover's old files. Theories that point to the possibility of such a change becoming permanent…."

Franky pulled Robin closer against him to hide his frown, sliding his grasp to the small of her back where he rubbed up and down soothingly.

Of course, he believed in Dr. Clover's research. After all, the man had founded O.H.A.R.A., and though Franky had never met him, he respected him greatly.

But Franky also believed in his friends.

"Zoro-bro's Zoro-bro," he eventually said. "He's a crazy dude, but….we wouldn't lose him to something like that. He wouldn't let it happen."

Robin closed her eyes, lifting fingers to grasp lightly at the open fabric of Franky's shirt.

Franky sensed her lingering apprehension, and he lifted hands to her cheeks, pressing a kiss to her forehead.

"Get some sleep tonight," he advised. "You've been stayin' up late all week. Sure you'll feel a-okay in the morning~"

It wasn't like her to worry like this, after all. Not since her days as a student could he remember her outwardly fretting this much.

He heard her sigh, but she tilted her head to kiss his jaw.

"Alright," she said. "Chopper is in the lab still. But once he leaves, I'll rest."

"Good," Franky replied with a smile. He leaned in to finally kiss her properly, pulling away only when he felt her hands give his waist a final pat.

"See you tomorrow, honeybuns~" he said, squeezing her hand one last time before he backed up towards the front doors and the parking lot beyond.

Robin crossed arms over her chest and gave one last elegant wave.

"Call me that again and you may not _live_ to see tomorrow~" she mused pleasantly.

Franky jolted, gave a sheepish laugh, then scurried to push open the doors.

"Roger that!" he conceded with a little salute before his kind-hearted girlfriend could crush his manhood or some similar punishment.

Robin chuckled to herself, watching him lumber up to his Hummer through the clear glass windows, the huge car managing to look average-size compared to his large frame.

Only when his headlights flicked on and he started to roll towards the exit did she finally turn and walk towards the Marine Mammals hallway, where a light still burned brightly, evidence that Chopper was indeed still working.

She moved through the doorway into the hall, fully prepared to gently order Chopper to go home too when, suddenly, the young man himself barreled out of the laboratory door, nearly colliding with her full-on as he sprinted towards the elevator in a frenzy.

"Chopper!" she exclaimed in shock, catching herself on the wall for balance. "What's-?"

"Zoro's locked in the research lab!" he shouted, already at the end of the hall, jamming his finger into the elevator button repeatedly. "I saw it on the security cam!"

Robin's eyes widened, and she hurried after him without a word.

* * *

The soothing rush of water over his gills. His heart beating steadily, placidly, in his chest. The vague feeling of fingers stroking through his hair, accompanying two quiet voices.

Eyes scrunched tighter, and he groaned slightly, for no apparent reason. He was no longer in pain.

But it elicited a reaction from his companions, a soft gasp and gentle hands squeezing his shoulder.

"Zoro! Can you hear me?"

It was Chopper's voice, and the fingers in his hair were definitely Robin's, enough that he wasn't surprised to find his chest and head resting against her legs where she sat on the sloping edge of the lagoon, water lapping over them softly.

" _Zoro, are you alright?_ "

He forced his eyes open at the sound of Robin's voice, in his own language, and he blinked a few times until eyes focused on Chopper's orange T-shirt just in front of him, the fabric wet and soaking.

" _M'fine,"_ he answered Robin, and to prove it, pushed himself up off Robin's legs to try and get his bearings.

"What were you thinking, Zoro?" Chopper asked, in a fair imitation of Johnny earlier, his tone scolding, but his voice quiet with nerves, his hand sliding down Zoro's bicep to clasp his forearm. "If I hadn't seen you…."

The merman looked away sheepishly.

He didn't have an answer for that. He'd been stupid. But he didn't regret trying what he had. Because there was one thing he knew for sure.

"He needs to see," Zoro said clearly, thankfully not stumbling over his words to hit home his point.

"What? Who? Who needs to see what?" Chopper replied with confusion, but when Zoro turned his serious gaze to Robin, it was obvious she knew exactly what he was talking about.

" _Him_ ," Zoro answered. "He needs to! He's - He - can help-"

A little growl of frustration before he gave up and lapsed into his own language, even if Chopper wouldn't be able to understand it all.

" _He's the only one who's gonna have any shot at negotiations with the M.A.R.I.N.E.S., and you know it,"_ Zoro insisted to Robin. _"We can't leave him in the fucking dark anymore. We know his head's in the right place. Hell, you even said that! I remember you said so after meeting him years ago - you could tell! So why can't we trust him to know everything?"_

He seemed ready to argue more if need be, but surprisingly, Robin's response was calm, her lips turning up ever so slightly.

"That was Dr. Red's decision, not mine," she reminded, then she leaned forward, switching to Zoro's language to say, " _Zoro, if you wanted the bracelet, all you had to do was ask~ Instead of nearly killing yourself to get it~"_

Zoro's mouth, already open to protest what would surely be _Robin's_ protest, only managed to utter a surprised sound, his eyes narrowing before a brow quirked up slowly.

" _Wait….what?"_ he stammered. _"But - what about - danger an' - all that shit? What about not trusting Curly Brow?"_

Zoro wasn't sure why he was voicing a counter-argument, but dammit, it was often difficult to decipher when Robin was using one of her reverse psychology tricks.

But to that, Robin merely sighed, shook her head.

 _"Was Johnny attempting to talk you out of it?"_ She clicked her tongue disapprovingly. _"I told him earlier he wouldn't be able to."_

Zoro opened his mouth to reply, but Chopper beat him to it, the young doctor looking between the two of them with growing confusion.

"What about danger?" he asked. "And what did Johnny say? I only caught...some of that."

"The bracelet," Robin replied easily, just before getting to her feet.

" _I_ will retrieve it," she said pointedly to Zoro, and turned on her heel to walk back towards the lab, just before the news sunk in for Chopper and he sucked in a sharp breath.

"The _bracelet?!"_ he shrieked, rounding on Zoro with wide, worried eyes. "But Zoro, what if it doesn't work! No one's even used it since-"

"Need to _try_ ," Zoro insisted, with enough power and intensity to his gaze that Chopper did back down, though he still wrung his hands in his lap apprehensively.

He didn't reply for a few long moments, looking worried all the while, so eventually, Zoro nudged him gently with an elbow.

"Chopper," he said. "About….Question."

Chopper furrowed his brow slightly.

"What's your question?" the younger man wondered, tilting his head.

But then Zoro gave a little growl and shook his head.

"No. _Question,"_ he repeated with more emphasis.

Chopper still looked confused for a moment before his eyes lit up finally with recognition.

"Oh! You mean Sanji?" he tried, and when Zoro relaxed some, nodding, Chopper asked, "Why not say his name?"

Zoro just shrugged.

"So…. _Question?"_ he asked again. "You _think_ ….?"

Chopper watched Zoro for a second, but then a small smile came to his face, thinking of the blond man's demeanor.

"Well, to tell you the truth, he reminded me a lot of _you_ ~" Chopper said, and giggled when, after deciphering his words, a look of mild shock, and then horror crossed Zoro's features.

Zoro stammered for words, which only made Chopper laugh more, the merman eventually giving up and letting Chopper have his moment of amusement.

Once the laughter faded, however, Chopper looked at him once more, mouth twisting a bit in thought before he murmured, "Just….be careful, Zoro. This is kind of how all of this started. Y'know….waaay back when the M.A.R.I.N.E.S. first found out about you guys and stuff…. I don't - I don't want-"

But despite his annoyance from a moment ago, Zoro reached out to place a hand on top of Chopper's head, gave a ruffle to his soft brown curls.

"Don't worry," he assured confidently because upsetting Chopper was out of the picture.

Chopper batted at Zoro's hand, but smiled.

The lab door clicked shut across the room, Robin striding over to the two with a gentle smile of her own.

Perhaps Franky had been right. Perhaps she'd been wrong to worry for Zoro's emotional well-being….

This was one instance when she hoped she was.

" _Do not lose this~ As far as we know, it's the only one left of its kind,"_ she said to Zoro when he looked up at her, in his language so he wouldn't miss a word.

She knelt before the water's edge and held over a thin silver band of metal, looped in a simple oval shape with two tiny sharp-looking prongs on the inside.

Zoro took the band from her, examined it for a second, then met her eye with a serious nod.

" _Good,"_ she replied, and made to stand again. But just before she did, a thought struck her, and she smirked.

" _Oh, and Zoro. Because I know your curiosity may very well get the best of you. Please wait until you're out of the water before trying it on~"_


	5. Becoming the Enemy

_Zoro was hungry. He'd eaten almost nothing for three days, save for a few small fish he'd managed to catch, since he'd woken up in this strange place, a place that looked like the ocean, his home, but wasn't. There was coral and rock stretching up to the surface, sand on the floor, and there were all kinds of fish darting about the space, but that was just it._

 _It was a space. An enclosed space. With strange clear walls that blocked him into a small area, trapped him, and when he'd spent far too long ramming against it, snarling and frustrated, trying to break through to no avail all around the perimeter, he'd very nearly broken down and cried._

 _It was hardly like him - hardly like his species in general._

 _Sharks didn't cry, even ten-year-old ones. Kuina wouldn't cry. Kuina would - she would-_

 _She'd been taken too._

 _The last thing he remembered before blacking out was the scratchy confines of a net biting tightly into his skin as he thrashed about desperately on the hot deck of a ship, screaming Kuina's name hoarsely as he watched his friend be dragged away in a similar net, shoved into a tiny pool of water, a heavy white door slammed over it an instant after she splashed down._

 _And then he'd woken up, in this place, his body temperature and his breathing stable, but his whereabouts unknown, save for one terrifying fact._

 _Humans._

 _The warriors had been taking the Princess to the surface to meet with humans for years. Why, he didn't know, apart from the fact that the late Queen had requested it, but how was Zoro supposed to believe there was any good in humans, knowing what happened to her family - and now to him and Kuina?_

 _It was humans holding him captive, and Kuina was nowhere in sight._

 _He'd seen the humans moving about by the surface, their bodies long and alien-like, looking like elongated starfish as they peered into the water, tried to coax him out. Some had even dove down, strange cylindrical rocks strapped to their backs and odd flippers on their split tails._

 _But he'd kicked an eel out of its lair and hid himself in a tiny alcove of the rock wall, refusing even the large tuna offered to him. Who knew what they'd put in it._

 _And he'd stayed there until the light had changed, because he couldn't see the sky above, only strange white lighting and an artificial blue that glowed from hot little globes in the water, hidden behind rocks and kelp. He'd stayed there until it got dark above him, though the water stayed illuminated, and he no longer heard foreign voices or saw those lanky forms lurking about on the other side of the walls._

 _So it was for three days, Zoro hiding when the white lights were there, only emerging when he was sure the humans were gone._

 _He knew he couldn't keep this up forever though. He had to find Kuina! And he had to eat something more substantial than the small bite-size tropical fish, also trapped like him, that swam around in circles all day._

 _It was the fourth day that Zoro finally grew hungry and desperate enough that he knew he had to do something. Had to escape, had to find Kuina somehow, because it was clear no one was going to help him. He was on his own._

 _That morning (at least, he had to assume it was morning, considering the bright white lights had started to shine above him), he slowly emerged from his protective hole. He debated making a spear, but there was nothing he could use to build it, so he'd have to settle for his teeth if things got violent._

 _He was scared. That much was obvious thanks to the pounding of his heart, and he hadn't realized how much of his courage was the result of Kuina's cool confidence. She was only a year older than him, but ever since that day, maybe a year ago now, when she'd saved him from getting mauled by a particularly nasty barracuda he'd foolishly tried to pick a fight with, it had been clear who was stronger._

 _He'd wanted nothing more than to match her strength one day._

 _But that day was not today. Because he was terrified the second he saw, oddly, a human's pair of tails slowly slide into the water, bare and dangling into the depths as the pair's owner sat on the edge of the water. He nearly darted back into his hiding place for fear they were going to try and swim down to him again, but this human didn't move, just sat there, swishing its tails absently back and forth._

 _He watched, for a long time, peering up and up at them with wide eyes that grew just a little more curious the longer the human made no effort to move._

 _Was the human alone? He didn't hear the familiar murmur of voices above him, speaking in a language he didn't understand, and he hadn't seen any other shadows moving about, looking for him from behind the clear wall._

 _Maybe this was why, after a good long while, he found himself slowly, tentatively, swimming his way up towards the surface, sticking close to the rocks and trying to move as sneakily as possible so the human wouldn't catch his movement._

 _He'd nearly made it to the top, higher than he'd swam since awakening here, still a few meters from the human, when he heard a gentle female voice, speaking to him in his own language._

" _It's alright, you know. No one will hurt you here," said the voice, and he realized, after a few moments, that it was the human who'd said it!_

 _Unbelievably, the human knew his language, spoke it fluently, with perfect pronunciation, and despite his wariness, his tail gave a few excited flicks of its own accord._

 _It took him another minute or so to work up the bravery to poke his head slowly out of the water, only his eyes though, just so he could get a look at the human._

 _It was indeed a female, one who looked young, older than him, but a teen perhaps. She was seated on the flat ledge beside the water, and he couldn't even begin to describe the space above him. It was unlike anything he'd seen before, almost completely white, and as he'd deduced, the sky was nowhere in sight, so he decided to focus on the human first._

 _His eyes didn't leave her, his heart still thumping hard, even though her blue eyes and soft smile were kind. Her black hair was tied up, and she wore a strange covering over her body, an outer layer of tight black skin that covered her shoulders and entire torso, half of her tails too. Merpeople often wore coverings as well, but nothing like that._

" _Your name is Zoro, right?" she asked him, again in his language, smiling when his eyes, still peeking above the water, went wide and he nearly ducked under again in alarm._

 _The girl chuckled, then added. "My name is Robin. Your princess has told me much of you and your friend, Kuina~"_

 _More shock and confusion, more questions bursting through his mind._

 _This human knew the Princess? The Princess had talked about him? Sure, he and Kuina were training to protect the palace, but he didn't think they were_ _ **that**_ _important._

 _Not to mention-_

" _Where is she?!" he finally blurted out, his head popping up the rest of the way, if only to reveal the angry snarl on his face. "What did you do to her?!"_

 _But her expression merely darkened considerably, smile falling off her lips, and she made a quiet noise, like when a dolphin or whale released air from its blowhole._

" _She's not here, I'm afraid," the human replied, voice full of regret. "She was taken...by the M.A.R.I.N.E.S….right now, you are at a place called O.H.A.R.A…."_

 _Zoro's fluttering heart just about stopped dead in its chest, the little merman's mouth dropping open wordlessly. Fearful eyes finally left Robin to flick around his current environment, seeing no sign of any living being in sight, no humans….and no merfolk._

" _What….?" he replied meekly, feeling his tail twitch nervously with the instinct to flee._

" _Yes," the human murmured, true sadness in her voice. "We have boats pursuing your friend as we speak. But it's been a few days, and I worry it will amount to nothing. As it is, we are lucky we managed to rescue you. When Franky's boat caught up, he only just managed to cut you loose from the netting before they sped away. They'd dangled you overboard, and I'm certain you would not have survived had Franky been a minute later."_

 _Zoro's chest shuddered, clenched hard. He felt sick, like he would if he ate something poisonous by accident, but with it came something he'd never felt before. He couldn't describe it as a word, but it was such a powerful feeling of loss and fear that it nearly rendered him immobile._

" _So she's…..gone…?" he squeaked out eventually, hating how weak he sounded, but unable to control it, not when he was facing the prospect of losing the most important friend to him…_

" _I don't want to jump to that conclusion," the human said quietly. "As long as there is hope, our rescuers will not give up their efforts. You, however, are very safe here."_

 _He was safe. He was safe and Kuina wasn't. That was the truth of the matter, wasn't it? Strong Kuina, who'd never let anything defeat her, was in trouble, and he couldn't do a damn thing about it._

 _His eyes burned, and he felt wetness sliding down his face that wasn't from the water around him…_

" _Why do humans do this?!" he heard himself yelling before he could stop himself. "We leave you humans alone! We don't do shit to you! But then you go and - and-!"_

 _The human watched him, listened as he lapsed into vicious noises that were halfway between snarls and sobs, his arms breaching the water to fist hands in his hair._

" _Get me out of here!" he cried, starting to sound more and more panicked. "I need to help her! Need - to-!"_

 _He couldn't finish, just darted under the water where he found the nearest clear wall and started ramming himself against it, rage and sorrow filling him, emotions he had never experienced to this degree, and he suddenly understood. He understood why the Princess was angry all the time, why she mourned so for the loss of her brothers, even though she couldn't remember them._

 _But what he didn't understand was her willingness to cooperate with humans, despite all of that…_

 _He punched and hit that wall until he ran out of energy, his limbs trembling, gills letting in desperate rushes of water as he struggled to get ahold of himself._

 _Slowly, he started to slide down the wall to the floor below._

 _But before he did, the human's voice sounded once more, muffled, but audible, above the water._

" _Not every human is an enemy, Zoro…" she said._

 _He gritted teeth, sinking down until his tail hit the sandy bottom with a soft puff of sand and bubbles._

 _Only there did he stutter out, "Like hell I'll ever believe you…"_

* * *

Zoro heeded Robin's words. He didn't let his curiosity get the best of him, keeping that bracelet safely tucked in the small pouch she'd clipped around his waist.

Chopper had laughed his ass off at the pouch, cackling about how he looked "so nineties," whatever the hell that meant. Robin had just smiled, a mischievous glint in her eye, ever the enigma.

And he'd set off on a course to B.A.R.A.T.I.E.

Yes, he'd pretty much left Johnny and Yosaku to believe he'd be going home, that he'd go talk to the Queen with them. But no. He had more important things to be doing, and if _Robin_ had given him permission, practically _urged_ him to do it? Then hell yeah, he'd take her advice over too-cautious Johnny's.

Besides, he trusted Sanji, not because he'd made the active decision to, but because he genuinely _did_. The blond was a pain, but he was nothing to be feared, and what Chopper had said to him...about the two of them being similar….

It was a gross thought, but if it were true, then that was all the more reason to believe Sanji when he vowed to help them. Zoro himself never backed down on his word, so that meant Sanji shouldn't either.

It was with this in mind that he made the long three-day swim back to East Blue, and honestly, he hadn't remembered it ever taking this long. The currents must have changed on him. It was also annoying to think just how right Sanji had been about boats being faster….they'd made the same trip in a matter of hours….ugh.

Three days afforded him time to hunt though, and after staying cooped up, thanks to his wound, even for a day or two, it was nice to get out and stretch his fins, feed properly on his favorites - tuna, mackerel, and the like.

For three days, he slept out in the open ocean, able to blink awake with a second's notice, should he be attacked, but most everything left him alone. He wasn't the same shrimpy youth he'd been, all talk and no bite. He was more than capable of taking care of himself now.

By the time he'd finally, potentially, arrived at the right location, it was evening, the daylight beginning to wane, orange seeping into blue. The water along the coast was warm because of it, as were the huge concrete breakers that he pulled himself up over, just to get a look at the other side.

The shoreline wasn't big, just a thin strip of sand that lined the lapping water before a clump of trees, their roots hanging down from the branches. He knew Robin had shown him pictures of such trees before, but fuck if he remembered the name.

In any case, the trees eventually trickled back into waving grass, which in turn was engulfed by sand dunes, and then there was a complex of buildings, buildings that looked similar to the outside of O.H.A.R.A., but were much smaller.

Robin had told him to look for a main building that was circular, two outdoor enclosure pools on either side, and a wide deck that jutted out from the building, a walkway between the enclosures, something he vaguely remembered from the morning they'd left for O.H.A.R.A.

Helpfully, there was a sign, he noticed, at the end of the dock, where two boats were secured, one with the B.A.R.A.T.I.E. logo emblazoned clearly on the side, and _yes_ , he could read that much, he insisted to an imaginary Curly Brow.

There was also no one around, only a few moving lights behind the trees which Zoro thought was one of those _road_ things that humans rode big-ass metal boxes on. Weird as fuck.

They were far enough away though that he wouldn't risk being seen.

Good.

Time to find a way past the breakers and get Curly Brow's attention….somehow….even if it meant splashing around and making dying seagull noises, as Chopper had suggested.

Okay, no, on second thought. Anything but that.

* * *

"I swear to fuck, Ace. This is such bullshit. You are not drunk already! You've had one beer!"

"I am _so_ drunk, Sanj, and _you_ are the best pillow if I pass out, so _deal_ with it~"

Sanji shared an eyeroll with Sabo, lounging sideways on the adjacent armchair, legs thrown over the armrest. The other blond was steering clear of his dumb brother, who was practically taking up the entire couch, just so he could use Sanji as a body pillow.

"Ace, I'm gonna kick your ass if you don't pick a racer already~" Sabo crooned in the same sugar sweet tone Ace had used on Sanji, scrolling through the colorful Mario Kart choices himself.

"Yeah! Me too!" Luffy piped up across the living room, where he stood, bouncing in place eagerly as if he were about to sprint a race rather than thumb-control through a virtual one.

Honestly, the only reason Sanji even had this game was for when these three losers came over.

It was a pretty rare occasion too, with all of their school and work schedules, Ace over at the Navy base, Luffy doing fuck knew what at his university, studies still undecided as they were, and Sabo getting his Master's in human rights and international law.

Sanji now wondered if merpeople rights fell under his jurisdiction...

Not that he'd mention anything about the merpeople, even to these three, his closest friends. He felt bad about it, and he desperately _wanted_ to talk about the fantastical madness he'd experienced three days ago, but he'd promised. He'd promised to keep it secret, and he would honor that for as long as he had to.

But still, he was absolutely _bursting_ to talk about it, and part of why he'd invited these three over (aside from the fact that his dad had actually gone _out_ for once - dragged to poker night at a local pub by Patty and Carne) was because he needed a fucking distraction.

He needed to get Zoro's stupid face out of his head, as it had kept him from concentrating on anything ever since they'd parted ways at O.H.A.R.A.

Why?

Even with Ace here, draped all over him. Even when he'd thought that, despite not being in a relationship for years, his lingering attraction for the freckled man could set his head straight…..

No. It seemed, somehow, Zoro had quickly nabbed Ace's spot, and _fuck,_ was that annoying when, merman or not, Zoro was an irritating bastard. Ace was lovable and endearing at least, on top of irritating. Zoro was just downright irritating.

But dammit, he was also intriguing, mysterious, and Sanji had been able to throw a level of banter at him which he couldn't dish out to many people without hurting feelings. Zoro's lack of language comprehension certainly came in handy when it came to insulting him, but there was just something about the merman's cocky smirk…..his lack of care or inhibitions…

Ace had sat up a bit beside him, now with an arm looped around Sanji's shoulders, though he'd picked up his game controller finally and started scrolling through playable characters himself.

Ace was a cuddly guy, with everyone, but particularly with people he was close with, something few might expect of the strong serviceman. But when things got serious, it was like a switch flipped within him and he became an entirely different person, playfulness gone.

It was something Sanji had always admired about Ace and his brothers, who acted much the same. They might have been goofy, but he could always rely on them, and Sanji found himself wondering if Zoro was similar.

Johnny and Yosaku had mentioned he was a warrior, and while he certainly looked the part, Sanji readily admitted internally that this was a mode of Zoro's he'd definitely like to see…

The brothers were arguing over which race course to choose, which was stupid considering everyone _knew_ it had to be Rainbow Road. And sure enough, a minute later, they were off, Ace finally releasing Sanji from his hold so he could properly get into the race, though, too far away to elbow Sabo or Luffy, Ace set to jostling Sanji about repeatedly in his enthusiasm.

They were a quarter of the way through the second lap when Sanji's phone buzzed in his pocket, the blond pulling it out with confusion for a second before he noticed it was an alarm he'd set earlier.

Eight o'clock. Already? Damn. He had to check on the turtles.

He gave Ace's shoulder a teasing shove as he uncurled himself from the couch and got to his feet.

"Aw hey, where ya goin'?" Ace asked, flicking eyes to Sanji only briefly as he continued right on with the race.

"Gotta make sure the turtles are set for the night," Sanji replied, stretching arms over his head absently before heading across the small living room towards the front door. "Shouldn't take long."

"Yeah, better watch it, or we'll drink all your booze~" Ace warned with a grin, steering his car furiously around a sharp turn.

"You will even if I'm sitting right here," Sanji fake-grumbled in reply, but there was a smirk on his face as he slipped on a pair of boat shoes by the door and headed out into the twilight.

He'd changed into street clothes for once, a pair of pale blue shorts and a loose pink button-down that he really liked but never had the chance to wear. He wasn't worried though, heading down the walkway towards the rehabilitation center. It wasn't like the turtles would splash him or anything.

He scanned his way in to the building, stepping out of the warm evening air into the cool air-conditioning, flipping on harsh lights as he went.

For the past few days, whenever he'd gone into the rehab room, he'd glanced at that empty tank where Zoro had spent the night, trying not to be _dramatic_ , but certainly feeling wistful about its lack of merman. It was like in third grade, when he'd gotten to take home the class hamster for winter break. When he'd brought it back to school, his bedroom desk had felt glaringly empty for a while afterwards.

Of course, he had to snort at that, comparing the dumb algaeball to a hamster. His brain was probably the size of one, to be fair.

He crossed the tank room, and for a few minutes, watched the sea turtles, particularly Beefsteak and Lettuce in the neighboring tank, both of which were the farthest along in terms of their recovery process.

Lettuce had a proper appetite these days, and Beefsteak was swimming strongly. He'd give it another week, and all four of the turtles, Cabbage and Spinach included, would probably be set for release, once they got Dr. Trafalgar to check on them one last time.

The vet was based up in North Blue, but he was the best of the best, so whenever B.A.R.A.T.I.E. had recovering guests, particularly large ones, they called him.

There were other benefits to having the tattooed doctor come all the way out to East Blue, benefits Sanji would never voice aloud. He'd been the second man Sanji had met in person whom he'd considered to be _criminally_ attractive, and even if the guy was weird, insisting _every_ time he came that they not feed the turtles any bread (something Sanji knew very well even without the doctor's warning), Sanji would excuse that.

Again though, as he watched the turtles circle about lazily, he had to wonder if Dr. Trafalgar knew anything about the merpeople too.

But no. He couldn't keep obsessing over this. He couldn't keep losing sleep poring over that database Franky had given him access to, soaking up everything he possibly could late into the night, thirsting for more even as his eyes fatigued.

It was-

Just then, a dull thudding sound and what sounded like a very faint grunt.

Sanji looked up immediately, eyes focused on a row of windows across the room that looked out at the docks where their boats were secured. That was definitely where he'd heard the noise, he thought, and when another thud and a splash, loud enough to be heard inside, cut through the silence, Sanji pushed off the edge of the turtle tank where he'd been leaning and strode over to the windows.

He shoved back a chair so he could reach over the lab bench more easily, pressing both hands against the glass to shield the fluorescent lights of the room from his vision.

Nothing. Nothing out of the ordinary, just the sinking of the sun over the ocean and the empty boats bumping gently against the dock with the water's undulation.

Still, the blond backed up and headed for the exit to the docks. He pushed open the rehab room doors into a darkening hallway that led to offices and a few research labs on the other side of the building.

Motion-activated lights turned on as he jogged lightly to another set of doors that slid open to the outside, onto the wide wooden deck that wrapped around the facilities in back.

He stood there, orange light sparkling over the water….and not a soul in sight, aside from the seagulls flocking over the breakers in the ocean beyond.

He waited, wondering for a moment if he should check the boats for a trespasser, but he could see they were empty from where he stood, and if someone tried to get in the building, it would set off an alarm.

Besides, it was clear he was alone.

Thirty more seconds or so….

The sound was gone.

Sanji finally turned to head back inside.

But that was when another out of place splash sounded behind him, and it was just loud enough to make him suspect something _live_ made it.

So he stopped, despite the very real threat of Luffy eating through his entire kitchen if he took any longer, because he'd been around water and around wildlife for enough time to know when a splash signified distress, and when he heard it again, more frantic this time, he knew he was right.

Sanji vaguely heard the door slide shut behind him, his mind already whirling through the possibilities of the noise's cause as he walked briskly down the dock, to the water's edge where he'd heard it.

It was quiet, save for the natural lapping of waves, yet he still knelt down on the edge of the dock, scanning the water with a trained eye for anything that might indicate what it was. The water was clean and clear, but it was getting dark, and that made things difficult.

Nothing. Nothing for a long moment….

Until, a hand, an actual hand shot out of the water, causing Sanji to shoot back in surprise, his heart jolting in his chest, but a scowl quickly forming on his face by the time a mossy head popped up after it.

Zoro. _Zoro!_ It was actually fucking him!

Excitement quickly replaced the shock, though he did his best to cover it up, even as his heart continued to flutter stupidly, growling out, "Ugh, it's _you?_ What the hell! You can't just creep up like that! You trying….to…...?"

Zoro had disappeared below the water's surface just as soon as he'd come up without even a word of greeting, and it was the way his hand reached almost desperately before sinking too that had Sanji trail off, staring down in confusion.

Without further thought, he grabbed Zoro's wrist before he could sink too low, pulling him back up so he could get a better look at him, in case he were injured again or something.

Zoro came almost limply, his torso flopping up onto the dock with no resistance, and the weirdest part was the way his body was twitching, spasming, choking noises leaving him almost like he couldn't-

Sanji wrenched the merman's head up, got a look at his gaping mouth, full of smooth, rounded teeth, his eyes which were unfocused, glazed over…..a dark brown...

Sanji gasped, scrambled to look over the edge of the dock into the water below, where he saw, instead of Zoro's tail….skin…..bare skin…..legs-!

"Holy shit, you're _human?!"_ Sanji shrieked, far louder than he should have, but dammit, he couldn't help it! "What the _fuck?!_ You're human! How is this-?"

He shoved Zoro over a bit onto his side, tried to get a better look, but his eyes went wide, and he quickly flopped him back over onto his stomach just as soon as he had.

"Oh jeez, you're naked," he blurted out in surprise. "You're human and you're naked and - what the hell, is that a _fanny pack?_ \- _Fuck-!"_

Thankfully, for Zoro's sake, he kicked into _rescue_ mode and sat back, slapping a hand onto Zoro's face again.

"Okay, _shit_ , okay - Zoro, you need to breathe!" he growled. "With your damn lungs - don't go all fish out of water on me - fucking hell-!"

Like hell he was doing mouth-to-mouth on this idiot.

"Right _here_ , stupid! Come on!" Sanji hissed, shifting his hand to press against Zoro's chest, but when that didn't yield a proper response, he made a noise that was now more worried than frustrated.

" _Fuck!"_ he cursed again, then shoved Zoro to his side and punched him hard in the stomach in a last ditch effort, something that….worked.

The merman took a gasping breath which quickly turned into coughing, water coming with it, Sanji pulling back his knee quickly to avoid _that_ mess.

Instinct seemed to finally kick in for Zoro, and Sanji relaxed some to the sound of his desperate, but continuous breaths.

"You're such an idiot," he said to express his relief, hand automatically rubbing over Zoro's back.

Zoro's recovery time gave him a minute for the shock to hit him again, the shock that _somehow_ , for _some reason_ , Zoro had made his way back here. And he was _human!_

It made no sense! Science aside (Sanji was beginning to accept the fact that science was far more fucked up and unbelievable than he'd ever assumed), how did he _get_ here?

Clearly, he couldn't swim or function as a human, so he must've come as a merman. But then if he'd somehow transformed here, _how?_ Had he done it voluntarily? Or had it surprised him just as much as it had surprised Sanji? Since when could merpeople even transform? Dr. Nico hadn't said _anything_ about that, nor had he read it in the research findings.

"What the _fuck_ is going on, mossball?" he murmured.

It took another minute before Zoro showed any movement beyond his breaths, but eventually, a hand shifted and planted itself onto the dock as he struggled to push himself up.

Dark, _human_ eyes met Sanji's, the former merman staring at him for a second, breathing heavily, before his lips turned up ever so slightly and he stuttered out a little raspily, "Qu - Question…."

"Yeah. Hi. Breathe _while_ you talk, dumbass," Sanji muttered, and tried to suppress that excited clenching in his chest that came right back when Zoro gave a breathless chuckle in response.

He _shouldn't_ get so excited about this. Just because Zoro was human didn't mean anything.

Suddenly, Zoro was pushing himself up more, trying to crawl onto the deck fully, and Sanji panicked.

"Hey, hey, whoaaaa, no! You stay down!" Sanji hissed, shoving at Zoro's shoulders. "You're _not wearing any clothes!"_

Zoro's eyes narrowed, flicked to Sanji's outfit briefly, then he craned his head to try and get a look under the water.

Sanji huffed out a breath, brought fingers up to pinch at his nose, then said, "Alright. Okay, _you_ just - stay right here, got it? Just like this! Do _not_ move! No going back in the water, and no coming out! I'll be right back!"

He took a moment to extract himself from underneath the algae-head (who'd sort of clamped himself onto his leg, he realized), then got to his feet.

Zoro stayed there, torso sprawled over the dock, though there was a slightly apprehensive look on his face, which he shot back at the water.

"I'll be _right back_ ," Sanji assured again.

Then, as if to prove it, he took off jogging for the building, pushing open the sliding door and scurrying into the first room down the corridor, flipping on lights as he went.

It was an equipment room, full of all sorts of gear, and along the wall hung a number of wetsuits.

He went down the line of shorts, surveying the sizes before ultimately deciding, with a bit of embarrassment, that Zoro would probably be a size larger than him, because he was _muscular_ , dammit.

He grabbed a black pair and rushed back out of the room, hoping he wouldn't arrive outside to find the dumbass drowning again. Or worse, lounging out on the docks, naked. Okay, maybe he had his priorities backwards there...

By the time he stormed outside, he had to pause in relief to find Zoro just as he'd left him, though he'd twisted himself and seemed to have one leg outstretched in the water, rotating it with interest.

He looked up upon seeing Sanji approach, then grinned and pointed at his leg.

"Weird," he said, to which Sanji rolled his eyes.

"Yeah, well, not as weird as having you show up like this in the first place!" he grumbled as he walked over to him. "You still owe me answers, y'know."

What he got was Zoro sticking his fist in his face when he crouched down beside him again, and he very nearly swatted it away, until he noticed the metal band encircling Zoro's wrist.

His brow furrowed, and he lifted a hand to take Zoro's wrist, brushing fingers over the metal.

"What's this?" he asked, and Zoro's grin grew.

"Changed," he announced unhelpfully.

Well, that clarified nothing.

"What? How?" Sanji pressed. Not that he expected Zoro to be able to explain any of it…

But, surprisingly, Zoro's grin turned downright mischievous, and he hitched a thumb over his shoulder towards the water.

"Tell if you come?" he said, and something about that question had Sanji's breath falter.

He fumbled for words for a second, blinking at Zoro slowly.

"Wait….." Sanji stuttered, his heart threatening to beat out of his ribcage now as an impossible notion hit him. "If I wear that….will I turn into a merperson?"

Why did he feel like he'd just won the damn lottery? Why was this suddenly the most incredible feeling of anticipation he'd ever felt in his life…?

"Probably," Zoro answered nonchalantly with a shrug, and the breath left Sanji in a shuddering exhale.

"H-Holy shit….."

There were no words. No words to describe how badly he wanted this, all childhood (and adulthood) dreams coming true in one fell swoop.

The things he could see. The things he could _experience_ \- what no other human ever had!

Limitless exploration. Discovering an entirely new world that not even the researchers at O.H.A.R.A. knew everything about!

If it was true, this…. This was….

"Dammit, mossball, you chose the _worst_ fucking time!" he screeched, shoving Zoro's shoulder, which only served to make the idiot's face light up gleefully.

But then his expression fell almost comically when Sanji hissed out, "No! I _can't!"_

It was ridiculous how readily the stupid fish-man wore his emotions on his face, something that the blond attributed to his animal blood. After all, sharks weren't very hard to read, doing what they wanted _when_ they wanted.

And Sanji didn't want that look of complete devastation on Zoro's face, especially when the shark-man could be his ticket to the undersea world, so Sanji dropped the wet suit shorts he still held and quickly grabbed Zoro's shoulders with both hands.

"No! _No!_ Get that look off your face! I want to! I _really_ want to! Shit, I want to _so bad!_ " A violent shake of the merman's shoulders to prove it, as if Zoro would revoke the invitation otherwise. "But I can't right _now._ I have _fucking_ friends over, dammit! I told you - it's the worst timing!"

Slowly, as understanding hit the merman, his grin slipped back into place with a relieved sigh and he even craned his neck to get a look at the building behind Sanji.

" _Human_ friends?" he asked curiously.

Sanji rolled his eyes.

"No, I called over some merpeople and they're all hanging out in my house-" But when a look of complete surprise came over Zoro's face, he smacked a palm to his forehead and cut the sarcasm. " _Yes_ , human friends."

What the fuck was he supposed to do? He could tell Zoro to take off the weird bracelet, transform into his normal shark self and come back later. After all, he couldn't afford for _anyone_ , not even his closest friends, to find out about the truth yet. He trusted all of them, but - well, Ace was in the Navy. And the Navy was a threat...

Still, something was niggling inside him, telling him he shouldn't give up this chance to have Zoro here - _human_. He didn't know what he was going to do with him - he couldn't even walk! - but the urge to get him out of the water was strong.

So he huffed out a breath, slapped hands down onto Zoro's bare shoulders decisively.

"And you're gonna have to pretend to be one of them!" he said.

He shoved the shorts at Zoro, who took them and began examining them, twisting them around until he figured out which way they went.

"Get up here. And put these on," he growled. "One leg in at a time. Pull 'em up to your hips. I swear to _fuck_ , do _not_ make me help you."

Zoro's eagerness was clear when strong arms finally pushed himself up onto the dock, flopping unceremoniously onto his stomach as he would if he still had a tail.

He turned though, and the second Sanji saw him start to flip to his back, he looked away, face bright red, staring hard at the building and the transparent door. At least he could see any movement inside, thanks to the fluorescent lighting, now brighter than the waning natural light outside. He'd have time to react before anyone discovered them.

But when he didn't hear any struggles of Zoro trying to get the shorts on, just various noises of surprise and snickers of disbelief, he growled loudly.

" _Zoro!_ "he said, keeping his eyes averted, but ducking his head towards the merman. "Shorts _on!_ _Then_ you can admire yourself or whatever!"

A high-pitched mocking of his voice, which just sounded like gibberish when Zoro couldn't repeat his language back perfectly, but he soon saw the correct movement happening out of the corner of his eye and heard the expected sounds of confusion and frustration.

It was only another minute, however, before he felt Zoro push him and growl, "Help."

"I told you no, mossball! You're _naked!_ And for humans, that's not-!"

Zoro just shoved him again, harder, nearly sending him off the edge of the dock.

" _Help,"_ he insisted, then grabbed Sanji's chin and used it to yank his entire body closer.

"Oh come on! Be _polite_ about it at least, asshole!" Sanji grumbled to hide his embarrassment. " _Damn_ , you're the worst…"

He reached out to snatch the shorts from Zoro's hand, turning them around so they were facing the right direction, glaring at Zoro the entire time.

It fucking sucked that wetsuits were hard as hell to get on for a normal person.

His eyes didn't leave Zoro's as he used his hands to stretch out one leg of the shorts, and dammit, the merman's lips had tilted up a bit, along with an eyebrow, and it was _no_ less attractive than it had been when he was a fish, perhaps even _more_ so with his slightly softer human features.

Fuck, this shouldn't be allowed.

"One foot in," he said levelly. "Your _left_ foot. You do know left and right, don't you?"

Zoro stared at him for far too long, still with that slow grin, before he finally broke eye contact to flail legs about, trying to both lift and coordinate his strange new appendage into the hole Sanji made.

"Shit, feel like I'm dealing with a toddler…" Sanji muttered to himself, rolling his eyes as it took Zoro far too long to finally get his leg in.

Once he did, Sanji decided the guy was going to have to learn how to do this, so he instructed, "Alright, now hold it open yourself, and stick your right foot through the other side, okay?"

He waited, watching Zoro expectantly when the merman lifted eyes to him once more.

But Zoro didn't take hold of the shorts right away. In fact, that same smirk worked its way back onto his face, along with a snicker when Sanji's lips pulled into an insistent line.

"Help," he said again, but when Sanji opened his mouth to screech, Zoro lifted his hand, clamping fingers onto Sanji's chin, quickly becoming a favorite place of his to grab, and pulled his head down.

Of course, this forced Sanji to lay eyes upon his still very naked lower half, if only for the reaction that followed - the unintelligible yelp, the flailing that left Zoro with the shorts looped around his ankle, Sanji with hands on the dock where he'd caught himself, on either side of Zoro's hips, and a scowl on his face, eyes firmly shut.

" _Fuck_ you!" Sanji shrieked, but winced, seemed to rethink his words, and quickly leaned back off of Zoro, amidst the sound of the merman's cackling.

"Why is it - _problem?"_ Zoro laughed, causing Sanji to groan, wishing his face weren't so embarrassingly red.

Why _was it?_ It shouldn't have been. They had the same parts. He was just being stupid.

But dammit, Zoro was-

Sanji shook his head, thought about the time Luffy had streaked across his college campus - how him, Ace, and Sabo went to pick up the idiot from the campus police station - to distract himself. Then he stretched out the shorts again and properly set about helping him, ignoring how well-endowed, by complete luck no doubt, the merman may or may not have been….

Zoro nearly kicked him in the face several times, and it _better_ not have been on purpose, but after awkward flailing, and some even more awkward positioning, Zoro was finally covered, still wearing that dumb fanny pack (where the hell had he even gotten that?). With how damn long the ordeal had taken, it was a wonder one of his friends hadn't come looking for him yet.

But then again, by this point, they were probably drunk out of their minds. He hoped this would work to his advantage when it came to explaining where the hell this foreign weirdo came from.

* * *

And Sanji sure as hell felt like he was dealing with a drunken idiot when he had to practically _drag_ a stumbling mossball all the way back through the building to his bungalow. Either that or a newborn giraffe, legs wobbling every which way, his balance all over the place.

Several times, he nearly took Sanji down to the ground with him, and dammit, Zoro was no wispy twig. He was solid muscle, as Sanji, thanks to some odd alignment of the cosmos, knew, and why he'd decided _Sanji_ was the only support mechanism he was going to use was beyond him.

Zoro was his exact height at least, which made things only slightly easier, but there was no way the blond was going to be able to give him a piggyback ride or some shit. That was ignoring the fact that it would look fucking weird as hell if he came back to the house in such a manner.

It took far longer than it should have, Sanji draping Zoro over the edge of the turtle tank at one point and trying to demonstrate how walking was done.

From there, Zoro got minutely better, but he still only managed to make it a few paces (leaning heavily on Sanji's shoulder) before starting on a collision course with the concrete floor.

So, countless curses and one arm nearly torn out of its socket later, Sanji _finally_ stood at his front door, the sky now the deep purple of coming night, Zoro grunting some broken complaint about the flagstone walkway hurting his bare feet - or so Sanji grasped from his caveman language.

"Would you shut up?" Sanji hissed, trying to keep his voice down, even though the competitive screeching from his friends inside, still thankfully engrossed in their gaming (fully grown adults as they were), drowned out his voice.

"If you'd learn how to fucking walk properly, this wouldn't be an issue," he muttered, nudging Zoro's waist to make him balance better.

"Not like - swimming," Zoro said, tentatively removing his arm from its near chokehold around the blond's neck to try and stand on his own.

"You think?" Sanji shot back, eyes on Zoro and hands outstretched to catch him if need be, even as he backed off a step or two during Zoro's attempt. "At least humans can do both."

Zoro just gave a condescending laugh and snorted, "No."

His arms flapped a bit to steady himself, making him look like some stupid penguin, Sanji thought, but, after a few seconds of freely standing on his own, he turned a triumphant grin up to Sanji, who, despite how exasperated he was, couldn't help but return it.

"Alright, now stay like that while I open the door, got it?" the blond said, smoothing out his shirt where Zoro had thoroughly rumpled it.

He reached out to fix Zoro up too, smoothing his damp hair into some sort of order, scowling at the fanny pack, _almost_ adjusting the black beads still around his neck before hands retracted, remembering Zoro's reaction before.

"You're an intern, okay? A foreign exchange student," Sanji dictated, formulating an entire story in his head. "You stayed late to help clean the tanks, but I invited you to crash here for the night. If Sabo offers to give you a ride when they leave, which he _will_ , just tell him it's cool but you're gonna need to be back here early tomorrow anyway."

He looked at Zoro expectantly, hoping for at least a nod of agreement, but the stupid blank expression on Zoro's face told him he'd understood none of the plan.

Great.

"Good talk," Sanji muttered sarcastically, then gave a sharp exhale as he turned back towards the door. "Just let me do the explaining."

And without further ado, he opened the door, just as Luffy cruised past both of his brothers in a Landship to victory, both Ace and Sabo protesting heavily that he'd cheated with a lightning bolt trick at the last second.

Sanji took advantage of the others' momentary distraction and ushered Zoro into the house, just in case he stumbled magnificently. But thankfully, he seemed to decide to be _good_ at walking and balancing all of a sudden, and Sanji managed to have him positioned normally, shutting the door behind him by the time the brothers noticed his return.

It was Ace who looked over first, at the sound of the door closing, an eyebrow raising at the sight of the shirtless man with a rather impressive red line across his torso standing beside Sanji.

"Whoa, who we got here?" he asked, a grin coming to his lips as he shoved Luffy's face away when the younger guy dove to tackle him for no apparent reason.

Sabo composed himself too, as soon as he realized another guest had arrived, though it took Luffy a few seconds longer to do so.

"Guys, this is Zoro," Sanji said casually, jerking his thumb over his shoulder at the man. "He's our new intern. Foreign exchange student at EBU. Forgot he was staying late tonight, so, mind if he joins us?"

Ace very nearly gave a very honest statement of his approval before Sabo elbowed him purposefully in the side, the wavy-haired blond getting to his feet first to cross the room.

"Nice to meet you, Zoro," he said, stretching out a hand in greeting. "I'm Sabo. If you're okay with a bit of chaos, it's no problem at all~"

Sabo's hand hovered between them, Zoro standing there staring at it for a second. His mouth opened silently, and his eyes flicked to Sanji briefly, whose smile grew a bit more fake and insistent the longer nothing happened, and for the first time since he'd transformed, Zoro realized he might be a bit in over his head.

He knew about the humans he interacted with, knew what to expect with them, but beyond that, he knew next to nothing. He was in a completely different world, not only for the physical changes - among them the weight of gravity, figuring out muscles he'd never had before, fucking _breathing_ \- but for, well, everything else.

None of this compared to videos. None of this compared to pictures. And so far, hardly anything made any sense to him, including that outstretched hand.

Sanji was flicking eyes frantically between this "Sabo's" hand and his, so, through his rarely used powers of deductive reasoning, Zoro slowly, hesitantly, reached out to take the man's hand.

But as soon as he did, the tension seemed to dissolve, Sabo grinning broadly and giving his arm a pump before releasing his hand again.

"Over there are my brothers, Ace - the one on the couch who's ogling you, sorry about that - and Luffy, who's - um, _excuse me!_ That was _my_ beer!" Sabo groaned when Luffy merely flashed a grin and a peace sign before chugging back the rest of the bottle.

An exasperated sound from Sabo, who threw up hands and shook his head, though he turned back to Zoro with a smile.

"It's nice for Sanji to have someone close to his age around here finally," Sabo mused. "Where're you from?"

"Uh…from…." Zoro started to say, but Sanji stepped forward, thumping the back of his hand to Zoro's chest.

"He's from-" But Sanji stopped too, snapping fingers as if trying to remember something. "You know the smallest country in the world?"

"Oh, you mean-?" Sabo began, until Sanji quickly interrupted.

"Yes! He's from a country smaller than that."

" _Smaller_ than that?" Sabo asked skeptically.

"Smaller than that. I forget the name in our language."

Sabo blinked at him for a second, then chuckled.

"Think we know who else gets smashed after one beer~"

"I am not _smashed_ ," Ace slurred convincingly from across the room, despite his earlier argument, and even though no one had addressed him. "Anyway, enough chit-chat! Get Shirtless Guy over here for another race!"

" _Shirtless Guy_ needs to towel off before he sits on my _couch_ ," Sanji said pointedly, and steered Zoro off towards the short hallway to his bedroom. "Come on. You can borrow some sweatpants…"

He tried to avoid looking at Ace as he led Zoro around the corner, the merman moving steadily, if robotically until they were safely out of sight.

From there, Sanji practically threw the guy into his room, Zoro having to catch himself on his desk chair….which swiveled and nearly sent him careening into the carpet below anyway.

Sanji just closed the door behind them, stood there for a second and closed his eyes, opening and closing hands towards his face in a gesture to compose himself, then set to tearing through his closet.

"I do _not_ want another wet suit debacle. So leave those on for now," he grumbled, more to himself than to Zoro at this point as he pulled out a pair of baggy black sweatpants with his alma mater's logo down the side and a plain white T-shirt, both of which he kept neatly on hangers.

Zoro watched him curiously for a second before getting a look around the small space, which was far more cozy than any human space he'd seen yet. In fact, this whole house of his was smaller and more intimate than anything at O.H.A.R.A. He had some idea of what human homes were like, having been shown pictures, but to think this room might be Sanji's personal space?

Something about that had him smirking as the blond approached him again.

Sanji took his arm and tugged him towards a flat rectangle against the wall - a bed, Zoro realized, and when he sunk down onto the cushiony surface, Sanji lowered himself to the ground, looping the dark fabric around his hands and shoving it over Zoro's feet with far more ease than the clingy fabric he already wore.

He ordered Zoro to lift himself so he could get it up to his hips, and despite how weird the softness felt on his skin, Zoro had to admit the warmth was quite comfortable.

Next, Sanji unclipped the pouch from his waist, tossed it aside and took the white fabric, which he found a hole in. Then he shoved Zoro's head through, forcibly lifting his arms to maneuver them through two more holes until his torso was covered as well.

He hesitated afterward though, his hands hovering over the outline of his beads, caught underneath the fabric.

But this time, Zoro didn't feel the urge to lash out at the possible contact, he realized. In fact, ever since he'd transformed, his usual tendencies to snap teeth, to bristle - be on the defense - none of those instincts were there.

Instead, he felt….calm. A little weirded out by everything, but calm nonetheless.

Was this really how it felt to be human?

"Can I-?" Sanji was asking quietly, fingers twitching towards the beads, and Zoro brought eyes to his face, noticed the way Sanji's brows drew in, almost apologetically.

The merman nodded in response, and Sanji let out a breath slowly, gently pulling the beads out from under the shirt and laying them flat over his chest once more.

Zoro didn't react, though he kept his eyes on Sanji until the blond looked up and met them.

He froze for a few seconds, but then shook his head slightly and moved back a step, shifting his gaze up and down the merman.

"Damn…" he huffed out. "You look…"

He trailed off, and Zoro quirked a brow at him curiously, leaning back on a palm to study him too while he waited for the blond to find his words.

Sanji had changed his clothes too, and there was something nice about the look, the way his shirt hung low and exposed some of his bare chest….

He only lifted eyes to Sanji's face again when the other man finally finished, "Human," with a disbelieving chuckle.

Zoro grinned proudly.

"Good human?" he asked, and again, Sanji laughed.

"I'll let you know after you make it through an evening with _those_ fools…"

* * *

If that was the test, then Sanji supposed, reluctantly, that Zoro had passed with flying colors. He'd parked the merman on the couch, _not_ allowed him any alcohol yet (that was an experiment for another day), and answered any too-complicated questions for him.

It was mainly Sabo anyway, who asked the intelligent questions, Luffy only wanting to know why his hair was green and whether or not he ate meat before deeming him more than friend-worthy and treating him just as he would if he'd known him for years. Which was to say, by the end of the night, he'd draped himself over the merman's shoulders, practically puppeting him through a race of his own.

Zoro looked thoroughly baffled through it all, having no clue what to do, and Sanji figured this was probably a good thing. Because he _was_ technically a foreigner. That wasn't a lie. They just didn't need to know he was foreign to the _species_.

On more than a few occasions, Ace had looked Sanji's way, subtly raising eyebrows or flicking eyes in Zoro's direction.

Sanji knew what he was getting at, and he'd passed him a roll of eyes, an insistent shake of his head, and a hard stare that said to drop it.

This only led the freckled man to shrug dramatically, holding up hands….then proceed to point at himself with a wiggle of brows.

Sanji smacked a palm to his forehead and dragged his hand down his face.

No moves were made that night, by Ace or otherwise, and by eleven thirty, considering it was a weeknight and Zeff would be back shortly, Ace and Sabo were up, with stretches and yawns and insistence that they do this again soon, preferably on a weekend when they weren't dead as fuck.

They'd dragged a suddenly very sleepy Luffy to the door, offered Zoro a ride, as expected, but ultimately bid farewell without incident, and moved to head out.

Sanji leaned against the doorframe, watching as Sabo threw an arm around Luffy's shoulders, the two starting off across the courtyard towards the gate that led to B.A.R.A.T.I.E.'s parking lot, where Sabo had left his car.

Ace, however, hung back, mumbling, "I'll just be a sec," to his brothers and lingering with Sanji just outside the door.

The warmth of the porchlight flickered over his teeth when he smiled softly at the blond once Sabo and Luffy were out of earshot.

Zoro was still inside though, so he kept his voice down when he murmured, "So...you and him..." He jerked his chin towards the house. "You're really not…?"

Sanji resisted the urge to respond with annoyance, or defensively at that. He hadn't given any indication of even faint _interest_ in Zoro he'd thought, so he had no idea where Ace had gotten this notion. Maybe the freckled man knew him better than he'd assumed.

Instead, he merely sighed.

"Ace, if we were, I would tell you. I just met him like three days ago."

"Yeah, but…" Ace trailed off with a low whistle, laughing when Sanji punched him in the chest.

"Would you be jealous?" Sanji asked with a grin, and he wasn't sure why he did.

After all, years had passed since he and Ace had belonged to each other, and while, most of the time, their chemistry now stayed firmly in the sibling category, it didn't help matters that they both had flirtatious natures.

Made all the more apparent by the teasing smirk on Ace's face, the way he leaned in closer to say, "Not if you invite me to the threesome~"

Sanji dropped his head back dramatically.

"Right, well, I'll call you in a million years when that happens," Sanji replied, lifting a foot to kick Ace in the stomach, the man stumbling back from the door.

"Night, Sanj," he said, raising a hand and giving a scheming laugh before he too headed off into the night.

Sanji watched him go for a minute, shaking his head before finally ducking back inside and shutting the door.

A heavy exhale.

They'd done it. Zoro had passed for human, and there was no way anyone had suspected….anything….fishy…

Sanji's heart jumped into his throat when he glanced back to find the couch completely empty. No Zoro in sight.

Sanji practically sprang into the room with a yelp.

"Hey! Zoro!" he called out, scampering to the kitchen, but finding that empty too.

Then it was down the short hall, and even though he was looking for him, Sanji nearly jumped out of his skin when he turned on the light in his dark bedroom to find the creepy mosshead standing in front of the full-length mirror on Sanji's closet door.

He was giving himself a full once-over, tried to stretch out a leg, but failed at balancing on one and nearly fell backwards onto the bed.

No harm done though because he snickered and finally lifted his head to Sanji, who let out a huff of breath.

"Don't go wandering off like that," he muttered, then crossed to his dresser to rummage through a few drawers, grab a pair of boxers and sweatpants for himself.

Normally he slept shirtless, but if his dad was going to come home to the inevitable sight of Zoro passed out on the couch, he wanted the least amount of implications that _anything_ suggestive had gone on, so he pulled out a T-shirt for himself too.

"Stay," he insisted. "I'm gonna change."

And he did, in the bathroom, washing his face, brushing his teeth, and tidying up the living room, ridding it of empty alcohol bottles. He washed the dishes from the spaghetti he'd made earlier, left the kitchen sink light on for his dad when he got in, and finally headed back to his room, closing the door behind him…

Only to find that his bed was very much occupied.

"Zoro! What the hell are you doing?! That's _my_ bed!" Sanji screeched from the doorway.

Zoro rolled his eyes, but lifted himself up enough to scoot closer to the wall to make space for Sanji on the small bed.

 _"What?!"_ the blond squawked, jaw dropping. "I'll get you a sleeping bag or something! Get the hell off!"

The stubborn merman still didn't move though, just buried his face in the pillow and whined.

Then he pulled his head up and groaned, "Ugh! Why! Tired!"

" _Because!"_ Sanji insisted, moving up to the bed so he could slam his palms down onto Zoro's back and give a hard bounce, shoving his weight onto him.

"It's! My! Bed!" he growled with each shove.

But when the third shove let up, Zoro took advantage, flipping over quickly so he could grab Sanji's waist and tug him down onto the bed.

"Just - _sleep!"_ Zoro snapped, nearly rolling on top of him in an effort to hold him down.

His forearm pushed the blond into the mattress, just as he'd held Sanji underwater the morning of their meeting, and the grin on his face was much the same, seeing Sanji struggle to be free beneath him.

"How do you expect me to sleep like _this?!"_ Sanji shrieked, finally managing to knee Zoro in the gut now that he had gravity on his side.

Zoro grunted and clutched at his stomach, giving Sanji an opening to knee Zoro off him until _he_ was the one holding _Zoro_ down.

He stared down at Zoro triumphantly, the merman's chest heaving with breaths he still wasn't used to taking, and Sanji hadn't even realized he'd thrown a leg over Zoro's waist to straddle him until it was too late.

Fuck.

This time, Zoro made no move to fight back, just lay there with a curious look on his face, even letting Sanji pin his wrists down on either side of his head.

Was this how humans fought for dominance…?

Sanji was watching his lips, he noticed, and for some reason, his instinct, in response to this revelation, was to run his tongue over them, something that made Sanji's breath hitch.

Shit, he liked that sound.

He bit his bottom lip, and Sanji made the sound again.

Damn.

"Zoro…" Sanji said, his voice sounding a bit odd in his throat before he swallowed, cleared his throat and tried again. "Do you…. _want_ me to sleep here? Is that what you're getting at?"

And it was the purposeful way he said it, the playful glint in his eye and the knowing quirk of his brow.

Zoro was almost certain he was mocking the question Zoro had asked him before he left O.H.A.R.A. three days ago.

The merman grinned.

" _No_ ," he replied, even though it was a lie, and his grin only grew when Sanji shot back a _"Yes!"_

Zoro snickered, and Sanji felt his heart do a little flip in his chest, a dangerous feeling because he _almost_ did it. He _almost_ leaned in and slammed lips to Zoro's, and dammit, he really _shouldn't_ have stopped himself.

But he also wasn't sure if he wanted to let himself fall into this too quickly, even if it was torture. Even if Zoro looked at him like he was something particularly good to eat, well - what if that was literally his thought?

Okay, no, Zoro wasn't going to _eat_ him, but - ugh, he didn't know _what_ Zoro felt or wanted, and maybe he could just ask him, but he also didn't know if Zoro even felt things like this….or if this human transformation was permanent….

Come to think of it…

His eyes drifted to the bracelet on Zoro's wrist, that thin piece of metal that had somehow caused all of this. He _really_ needed to call Dr. Nico about it in the morning…

"You're not gonna - turn back into a merman at midnight or anything, are you?" he asked cautiously, a tiny bit worried Zoro would die or something if they both slept through it.

But Zoro looked to his wrist, to Sanji's fingers, pressed there against the soft skin, just below his pulse point.

He shook his head, still studying Sanji's hand.

"Bracelet's on," he said simply, and Sanji rose a brow.

"So as long as that thing's on, you're good?" he asked, and Zoro nodded, so he sighed. "Then don't take it off in your sleep or some shit."

With that, he finally rolled off Zoro and got off the bed, watching as the merman shifted and made himself comfortable….which meant lying there flat on his back like a dead body.

It made some dumb kind of sense, Sanji supposed. He was used to sleeping weightless in the water, so why would he feel the need to curl up at all?

Still, Sanji had to scoff.

"At least get under the covers, idiot," he said, and when Zoro only furrowed his brow in confusion, the blond huffed and reached out to tug at the blankets underneath Zoro, eventually grabbing his shoulder and physically trying to roll him off the bed, considering Zoro didn't seem to have any idea what he was doing.

"Get up, get up, you damn oaf - come on-"

And he managed to get Zoro up….though the merman nearly tumbled right to the ground as soon as he put weight on his new legs.

"Honestly, did you forget how to do this _already?"_ Sanji muttered, just barely managing to steady the fool.

And he also managed to get the covers pulled back, with Zoro practically hanging onto his shoulder, finally shoving the merman back down to the bed, where he forgot to catch himself and flopped stupidly right onto his face.

But, soon enough, Zoro was properly flipped over and under the blankets, eyeing Sanji expectantly, especially as he moved over towards the wall to make more room on the bed again.

Sanji stood there beside it, staring down at him, wondering why this was such a big deal in his head, why he was reacting like a silly embarrassed teenager. Zoro didn't care. Zoro didn't even _know_ what implications this held, probably. He was a fucking fish!

This was the thought that finally drove Sanji to make a small determined noise, grabbing two extra pillows and planting them in front of Zoro as a wall, much to the merman's confusion. He just hoped Zoro had the common sense not to roll into them and suffocate in the night.

Before he could stop himself, Sanji got in beside him, turned on his side away from Zoro and reached over to turn off the light on his bedside table, plunging the room into darkness.

Silence for a long minute.

Then, a huff from Zoro, and, with a roll of his eyes, Sanji heard Zoro shift, squishing down one of the pillows between them so he could try and look at Sanji.

"I'm not _naked,"_ he grumbled, not understanding Sanji's apparent aversion to sleeping beside him if that weird taboo part of human culture was removed.

Sanji didn't move, but Zoro heard him release some air, a noise that somehow managed to sound disparaging despite having no words.

He watched what he could see of Sanji's face, his jaw, the moonlight filtered through the strange blue coverings he'd pulled across the windows earlier casting a light over him that _almost_ seemed reminiscent of the water. It was somehow comforting, given how fucking foreign everything else was at the moment.

Was Sanji going to ignore him?

But no, a second later, the blond's voice spoke quietly.

"Why did you come here, Zoro…?" Sanji asked, and the only reason Zoro hesitated to answer was to figure out how to say it in Sanji's language.

"To bring you," he eventually settled on.

Again, Sanji went quiet, and it was for long enough that Zoro wondered if he'd fallen asleep.

He sighed, then rolled over onto his back once more, staring up at the ceiling above him.

"Why _me….?"_

Sanji's voice again, confused this time, and Zoro knew he must be, but he also knew things would make sense if he brought him back to his world.

"Wanna - make sure," he answered, and the frustrated noise Sanji made had him smile a bit, even if the blond didn't look over.

"Make sure of what?" Sanji pressed.

Zoro shrugged and for the first time in his life, _properly_ yawned as a human.

"Make sure it's you," he said simply, and closed his eyes.

Another growl from Sanji, and he heard the blond sit up a bit.

"What do you _mean?"_ Sanji insisted, but Zoro kept his eyes shut, fatigue overtaking him.

He didn't move, didn't reply, and only when Sanji flopped back to the bed with a groan did he allow lips to turn up ever so slightly in a smirk.

He honestly did fall asleep after that. So he didn't stir when the backs of Sanji's fingers found his jaw again, just gently.

* * *

 _ **M.A.R.I.N.E.S. Laboratory Headquarters, North Blue**_

* * *

The sound of a throat clearing from the office doorway, and she looked up from the papers strewn across the desk to see the captain standing there, his shirt open and his silver hair slicked back smoothly. The only thing missing was the pair of cigars he normally had perched between teeth.

She turned down the volume on the laptop, which was playing a mellow rock mix to fill the silence, and set down her red pen over the circle she'd just drawn on the headquarters map, around the controls box she now knew to be located on the outside of the building, near the large outdoor enclosures.

"Is everything alright, sir?" she asked, pushing up glasses with a finger, tucking a lock of blue-black hair behind her ear.

The captain shrugged, eyeing the desk for a second before grumbling, "Surprised you're still here, is all."

She smiled a little sheepishly, then made to tidy up a few things, move spare pens back into their respective drawers.

"My apologies, sir. I was just trying to get my bearings," she admitted. "I must say, I miss our old offices back at G-5."

The man sighed, his gaze falling on the yet unpacked boxes that still lay strewn around the rather barren room.

"You'll get used to it," was all he said before he turned on his heel. "Tomorrow we'll discuss the specimens' situation. So don't stay too late."

And then he was off, leaving her to murmur, "Of course, sir," into the empty space.

She waited until his bootsteps disappeared down the hall outside.

Then she shut down the laptop entirely, pushed back the chair and stood. She maneuvered her way out from behind the desk, a little clumsily at first, nearly tripping over a box, but righted herself, her steps growing more confident as she made for the door and flipped off lights.

The door closed behind her and she heard the light click and whir of the automatic lock.

Looking left and right, there was no one in sight. Unsurprising, given how late it was.

Still, just as a precaution, she pulled down the sleeves of her floral print shirt over her wrists a little more and set off down the hall towards the enclosures.

Of course, she ignored the muffled cries coming from behind her, from inside the office closet.

She had her own agenda tonight.

* * *

 ** _Author's Note_** ** _:_** _If you're interested, I've been posting artwork to go with this fic (and all my fics) over on AO3 (same username). Feel free to check it out~_


	6. Releasing the Beast

Sanji awoke to the sound of snoring, something that, for a moment, made him forget entirely where he was, panic filling him, particularly when eyes shot open to find someone _sleeping beside him._

It lasted but a second though before he remembered it was _Zoro_ , but with that realization came a whole new array of things that set his heart pounding.

First of all, of fucking course he snored. As a merman, Zoro probably never had in his life, but as a human? He just seemed the damn type.

Still, this, admittedly, wasn't too annoying right now, because it meant he _was_ still human, and his dumb fish brain hadn't forgotten to keep him breathing all night.

Second of all, Zoro hadn't shifted in the night, still flat on his back. Only his head had moved, turning towards Sanji, which meant the blond had awoken to Zoro's gaping mouth in his face.

Because _Sanji_ had certainly shifted, somehow, and this was what had him frozen entirely, not wanting to budge an inch for fear of waking the merman.

He'd rolled to his side, facing Zoro. He could _feel_ his leg brushing against the mossball's, and even if it was through the fabric of his sweatpants, the fact that their thighs were touching was a little unraveling.

Worst of all, he'd smushed down the pillows between them and had his hand on Zoro's chest. He couldn't remember putting it there, and he certainly _wouldn't_ have, but there it sat, curled comfortably over his borrowed T-shirt, rising and falling gently with Zoro's breaths, the faint thud of his heartbeat beneath, if he concentrated hard enough.

It might as well have been the tick of a bomb though, with how rigid Sanji went, suddenly entirely aware of every involuntary _twitch_ his body made.

What would even happen if Zoro woke up? Would he attack him again?

….

Well, so what if he did?

He shouldn't worry.

But there he was doing just that.

The sun was out too, creeping through the curtains, and though he couldn't see the time, it was obvious he'd slept through his alarm for the first time in fuck knew how long. Shit. On top of everything, his dad was going to kill him.

He moved, finally, carefully removing his hand from Zoro's chest. No reaction, even as he slowly moved his leg as well, taking away the soft pressure of his thigh against the merman's.

Again, no reaction. In fact, Zoro's snores grew louder, if that was even possible.

Sanji's heart was still doing cartwheels in his chest though when he sat up, twisted to grab his phone off his bedside table.

Sure enough, it was a good forty-five minutes past his usual wake-up time, and he realized why. He'd forgotten to take his phone off vibrate the night before...

But even still, he was a pretty light sleeper. He should have woken up…

A quiet groan as he squeezed eyes shut, tapped the device to his forehead, then glanced back at Zoro.

Should he leave him here? Start attending to his duties? Apologize to his dad, who was no doubt up already and grumbling about having to cover for him?

But, quickly, his mind flashed to all the trouble the algae-head could get himself into, any _number_ of things, considering he knew next to nothing about the human world.

Images of Zoro trapped in the fridge, drowning in a puddle, electrocuted by a hair dryer…

"You are _such_ an idiot," he muttered aloud to the sleeping merman, for the millionth time, as if he'd actually done all those things, but it was becoming somewhat of a ritual.

And with that completed, he decided to at least get a headstart on getting ready for the day, given that he'd probably have to help Zoro through practically _everything_.

Just as delicately, Sanji peeled back the covers and slid himself out of the bed, watching Zoro's slack features the entire time.

He moved the pillows away from Zoro's face, disturbed to find a whole lot of drool on their underside, and tossed them aside with disgust.

Zoro's hair was mussed up every which way, even though he'd hardly moved from his original position, but it was ridiculous enough that Sanji's fingers itched to reach out and fix it.

He stopped himself.

Instead, he stared at Zoro for a long moment, wondering why it looked so completely natural to have the merman sprawled there in his bed.

Fuck.

He ran a hand back through his hair, huffed out, "What the hell did I get myself into," and turned on his heel to get ready.

* * *

By the time he'd showered, dressed (back into his work clothes, varied only by a teal polo now), and stood in the kitchen with a cup of coffee, reading a note left by his dad, there still wasn't any noise from the bedroom, save for that snoring. And seeing as it was pushing seven thirty now, which was fucking _late_ for him, Sanji wondered if he should go wake the lazy asshole up.

His dad had already headed out, left that short, but definitely annoyed note saying his son had missed his chance to join him, Patty, and Carne for a final tagging run of the local swordfish and that he'd have to stay behind and mount the sea forest specimens from the diving trip the day before to microscope slides. A fucking boring-ass job that no one liked to do, but Sanji supposed he deserved it for sleeping in as late as he had.

But he'd blame that on _Zoro_ if he had to.

It was for the best. With no one around for a few hours, he didn't have to worry about explaining Zoro's arrival, and he could easily hide any mishaps that happened along the way.

Before he did anything though, he wanted answers, so he whipped out his phone, quickly found Dr. Nico's number, and called it, bringing the phone to his ear.

It was still early, but considering the odd hour she'd been awake when Zoro had called her the other day, Sanji had to imagine it was okay.

The phone rang…...and rang…..and rang…..and he soon realized she wasn't picking up, confirmed when it went straight through to a voicemail system a few seconds later.

Well, it wasn't too strange. She could be out doing research like his dad, or, more excitingly, dealing with some merpeople.

"Good morning, Dr. Nico," he said after the recording beep. "This is Sanji Red from B.A.R.A.T.I.E. First of all, thank you so much for the other day. It was - pretty amazing, honestly, um-"

Sanji couldn't help but let out a breath on a grin.

"Anyway, I just wanted to let you know that Zoro is here, and he's, uh - well, he's _human_ , and-? Um, little confused right now, so if you could call me back on my cell when you get the chance, I'd appreciate it. Thanks a lot. Bye."

He hung up then, with a sigh, and slid his phone back into his shorts pocket.

He didn't know why, but by the end of his message, he wondered if Robin hadn't answered on purpose….

But that would probably be assuming way too much, so he shook his head, gulped back the rest of his coffee and decided.

It was time to wake the sleeping beauty in his room.

Unbeknownst to him, Zoro awoke to the same feeling of panic as Sanji had, albeit for very different reasons, namely that he _completely_ forgot he was human and, thus, upon regaining consciousness, forgot to breathe for a few seconds.

An awful constricting in his chest, a burning there that had him clutching at the _fabric_ that he was surprised to find over his skin, his arm feeling heavy because he was _out_ of the water.

Eyes shot open to see a white ceiling above him, felt soft, dry textures all around him, light coming in through a covered window…

A loud gasp as he finally remembered how to breathe again, gulping in heavy breaths for a minute before he pushed up to his elbows, threw aside the blankets, and stared down at his two legs, still there - not a dream.

" _Damn…"_ he muttered in his own language as he caught his breath, not even thinking about the fact that he was alone in the room, instead reaching out to run hands over the legs, carefully pull one in towards himself so he could roll up the ankle of the pants Sanji had given him.

Fingers brushed over the skin that felt the same as his upper body, but was still so _odd_ to have down there. He noticed too, for the first time, the faint scar that encircled his ankle, same as the one around his tail that he'd had ever since the M.A.R.I.N.E.S. had netted him and snagged it.

From there, fingers migrated to his foot, feeling each toe, snickering at how creepily it resembled a deformed hand. It was pretty gross actually, but it was incredible enough that he wasn't too put off by it.

A minute spent examining his legs, experimenting with how far he could bend them before it hurt, trying and failing to get one behind his head, before eventually directing his attention to the room around him, the sensation of sitting above water without feeling like his skin was burning as he dried, without that horrible closing of his gills.

Instead, he closed his eyes, took a deep breath, compared the rejuvenating feeling to a rush of water through his gills. He let out the air slowly, then inhaled again and found he liked it. It was relaxing, and if he concentrated, his senses heightened. He could feel his heart beating slowly, his head clearing and-

"Oh, you meditate now?"

He cracked an eye open to see Sanji in the doorway, and the way his arms were crossed over his chest, one hip leaning casually on the doorframe, had a stupid grin forming on the merman's face.

Yet another good thing about being human. This stupid guy.

"What?" he mumbled, not understanding Sanji's question, but the blond just shrugged with a smirk and pushed off the door to walk to the window, where he pulled back the coverings to finally let the proper morning light in.

"You hungry?" Sanji asked. "My dad already left with Patty and Carne, so we're on our own. I can make breakfast?"

Zoro tilted his head and quirked a brow.

"Make…?"

This, admittedly, had the blond snicker, and he reached out to ruffle the mossball's hair as he walked past again.

"Humans are _sophisticated,"_ he said, purposefully using a big word so Zoro wouldn't understand and have a chance to counter. "We _prepare_ our meals instead of just chomping any old thing we see~"

Something about Sanji's tone though brought a surly scowl to Zoro's face.

"Anyway," Sanji added. "First thing's first, there's some fucking hygiene things we need to cover, so get up. M'gonna show you what's what in the bathroom, but I am _not_ helping you with anything in there. You're on your own and I mean it."

He stood in front of Zoro then and offered his hand out to ever so kindly help him up.

Zoro stared at it for a second, and though he didn't understand the context, he definitely recognized the gesture.

And, just as he'd figured out with Sabo the night before, he reached out and gave Sanji's hand a shake, a smug look on his face. See? He wasn't so bad at this.

But Sanji just looked at him like he was a _complete_ idiot, much to Zoro's confusion.

"Cute, but - no, mossball," he huffed. "I said _get up_. I'm _helping_ you."

And he gave a tug to Zoro's hand to illustrate.

Zoro frowned, annoyed with the mistake, but he did slide forward to dangle legs off the bed, tentatively touching feet down onto the soft carpet.

Sanji tugged his hand again, and he slowly stood upright, this time determined not to fall as he put more and more weight onto his new legs.

"Good," Sanji muttered when he managed to stand straight for a few seconds. "Now, remember walking? One foot, then the other…."

He kept hold of Zoro's hand firmly, backing up a step when Zoro did as told, concentrating on shifting his weight to one side so he could lift the other foot.

One step, but then he faltered, though Sanji caught him, a hand clamping onto his forearm.

"Don't think about it so much. Just do it naturally," Sanji advised, and backed up again. "Here. Look at me, not the floor."

He gestured to his eyes, waited until Zoro met them, then started slowly moving backwards, the merman's intense gaze fixed on his as he followed.

It felt like a dance, Sanji thought, as he moved in time with Zoro's steps, eyes on each other, and by the time they reached the door, Sanji grinned and lifted both hands to show Zoro he'd let go, that he'd done it on his own rather effortlessly.

Zoro saw his hands, realized what it meant, and the flash of accomplishment in his eyes that accompanied his smile was enough to make Sanji's heart flutter just a little.

A few more steps into the small hallway, and they'd reached the bathroom, where Sanji flipped on lights.

From there, it was a ridiculous tutorial Sanji had _never_ expected to give a grown-ass man. Or merman, for that matter.

He showed him the sink and the toilet, told him what each was for and that under _no_ circumstances could their uses be switched.

He found Zoro a spare toothbrush he had in a drawer from some hotel, taught him how to brush his teeth, which the merman _hated_ , saying the toothpaste was bad, but Sanji didn't care. Zoro may have, by some genetic miracle, had some enviably pearly whites, but he would _not_ tolerate fish breath.

Next was the dreaded shower, which was probably the contraption that baffled Zoro the most, but, again, Sanji insisted that, so long as he was human, he had to follow protocol.

So he'd helped Zoro strip out of his sweatpants and shirt at least, got the shower running for him, and showed him the various soaps. He got him a spare towel, told him to _use it_ and _not_ to take that damn bracelet off.

At that, Zoro's look turned downright skeptical, glaring at the spray of water coming down from the nozzle.

"But - _water_ ," he said, like it would burn his human skin off, and Sanji rolled his eyes.

"You won't drown in the _shower_ ," Sanji assured. "You submerged yourself before, and that was a dumb move for someone who can't swim in this form."

Zoro's mouth opened, like he was about to protest, but he ultimately chose the smart move and kept it shut.

Sanji smirked and patted his shoulder.

"You'll be fine, idiot," he said, and moved towards the door. "I'll leave the door cracked. I'm just gonna be in the kitchen. Remember. Shower. Sink. Toilet. Do not mix."

"But-!" Zoro started to say, though Sanji cut him off.

"What, are you _scared?"_ he taunted.

This earned him the reaction he'd hoped for, determination and focus sharpening in Zoro's eyes.

"No!" the merman insisted, and even shoved Sanji's shoulder for good measure. " _Bye."_

He'd show him! He knew what he was fucking doing!

* * *

He had no idea what he was doing. He realized that very quickly after Sanji left.

He peeled off those stupid shorts, putting himself in all kinds of compromising positions to do so, unbeknownst to him, having to get on the floor, but he'd done it. And, when he'd tried to get back up, he'd nearly yanked down the weird-ass sheet things hanging from a bar across the shower, but whatever. They had bad pictures of fish on them that looked nothing like the real things, and therefore, they were dumb and ugly.

He'd cursed a _lot_ , but not in Sanji's language, so the blond wouldn't understand him if he overheard, and eventually, he was standing under the stream of water, concentrating _very_ hard on not slipping and smashing his face into anything. Fuck gravity.

From there though, everything else Sanji had told him about which things to use on his hair and body were completely forgotten, and he stood for a good five minutes trying to decipher the array of bottles hanging from a wire contraption around the shower nozzle.

Eventually, he gave up and just chose one, pushing down on the top like Sanji had shown him….only to have a stream of gel nearly nail him in the eye like some projectile.

He cursed, wiping the substance off his face, but then decided to just start rubbing it through his hair to get rid of it.

It lathered, creating a mass of bubbles, and when he sniffed at it, it smelled just like Sanji's hair had last night, like clean sand and ocean spray, so he had to assume he was on the right track.

He spent a few minutes playing with it, spiking his hair up in weird ways before he got bored and stuck his head back under the water to rinse it all off.

Now what?

Zoro stood there again, staring at the bottles, but he really didn't want to try and figure out what each one said, so he just took some of the same soap stuff and started lathering it over his arms and torso like Sanji had told him.

It felt kind of gross and slimy, but this was apparently what humans did.

As for his bottom half, he slowly lowered himself down to sit on the floor, which he probably should have done from the start because it made things _so_ much easier.

He scrubbed around down there for a while, examining new parts. Then he scooted under the water and just kind of sat there for a few minutes.

Oddly, it didn't feel as refreshing as it normally did. The water was warm, but the longer he sat there, his skin began to feel somewhat raw, and his fingertips wrinkled creepily. He did not like that. Not to mention, the steam started to feel a little suffocating. And there was a foreign feeling in his mouth and throat...like they were dry? He'd never felt it before.

Damn. Humans really couldn't handle water.

He was tempted, just for a moment, to take off the bracelet and revert to his normal form, but he figured Sanji would kill him, and he might also kill himself.

So he latched onto the short wall of the tub and carefully got himself to his feet again.

He had to turn the water stream off, right?

This he could probably do. There were only two nozzles, and even _he_ could figure out that the one with the red band around it meant 'hot' and the blue one meant 'cold.'

Well, he wanted the hot water gone first, so he turned it one way, only to get blasted by a scalding stream that had him screech and nearly tumble over in his flailing to turn it the other way.

Same mistake with the cold, an icy jet almost freezing him to death before he managed to get that one off too.

He stood there after, soaked and panting, and for the first time in his life, he _wanted_ to get dry.

A scowl on his face, he hunched shoulders and pulled back the stupid fish curtain, took one look at the clothes scattered on the floor that he was supposed to get back into, and decided like hell he was doing that right now.

So he grabbed the long blue rectangular cloth that Sanji had pointed out as a 'towel' and proceeded to rub it all over himself as he'd seen Franky do when he got out of the water after diving sometimes.

He threw it around his neck, slowly climbed out of the tub, and strode out of that damn bathroom without a second thought, thankful for his growing skill with walking.

It wasn't entirely smooth though. But, after a few stumbles and a few wrong turns, once into Sanji's room, and twice into a tiny cave-like room with shelves and more towels, he finally found himself back in the room from last night, with the TV and chairs and shit.

And Sanji was standing in another half of the room, separated by a long flat slab thing, cooking something over one of those fire tables.

He smirked and headed closer, surprised when his feet slapped down onto a harder texture than the soft tickly carpet.

The blond looked up at the sound of bare feet on tiles, about to snark a quip about Zoro's time in the shower and how commendable it was that he managed to walk the two steps from the bathroom to the kitchen…..that is, until eyes traveled immediately downward, widened….

And then, the screech.

" _Zoro!"_ he yelped, abandoning his post at the stove and zooming across to the man to whip the towel off his shoulders. "I told you! You can't just go around _naked!"_

He had the towel unfurled and bound around Zoro's waist in a matter of seconds, infuriated by the nonchalant way Zoro just shrugged.

"Forget," he said, confused when Sanji suddenly started inspecting his head.

"And you've got soap behind your ears - _ugh!_ Come here!"

Sanji clamped his hand around Zoro's wrist and dragged him to the sink, where he pulled out the small nozzle and shoved Zoro's head down so he could rinse out the rest of the suds.

It was definitely shampoo at least, so Zoro had miraculously gotten _something_ right.

" _Fuck_ , mossball, come on," he complained when he finally released the idiot.

Maybe he should have been more patient and understanding, given how everything was new to the man…

But this was _Zoro_. He could take the abuse.

"Done?" Zoro grumbled pointedly when Sanji let him go, to which Sanji shot back, " _No!"_

But he did concede somewhat, moving back to the breakfast he was currently preparing.

"You still need clothes," he said over his shoulder, prodding tongs over a pan of sizzling bacon. "But it can wait until after breakfast, I guess."

Not merely an excuse to let Zoro walk around shirtless.

"Water thing…..hated it," Zoro was mumbling, having come up beside Sanji to spy on what he was doing up close. "Too hot. Felt….weird."

"Yeah, well, at least you smell good," Sanji replied absently, only realizing a second too late what he'd actually said.

He froze, midway through placing a finished piece of bacon on a serving plate, feeling his heart jolt and a heated flush spread over his entire face and neck.

Zoro seemed to think nothing of it though, the merman leaning in, a finger creeping ever closer to the fluffy yellow cloud of cooking scrambled eggs.

Sanji regained himself just in time to swat his hand away.

And in fact, he had to do so several more times before the meal was finished. Thankfully, this gave Sanji a thorough distraction from how _nice Zoro smelled_ , among other things. _Fuck_ , he couldn't believe he'd said it out loud…

It wasn't until he had the merman sitting across from him at the small table in the center of the kitchen, steaming plates of a damn good-looking breakfast in front of them, that he realized there was a whole new lesson to be taught on _eating and drinking._

How did he even begin to explain not choking, something Zoro had likely never had to worry about thanks to not having lungs? He knew mouth or throat blockages were still a hazard for fish, but certainly not in the same way it was for humans.

And that didn't even cover _drinking._

Sanji's hand shot out the instant he saw Zoro's fingers reach for the food on his plate.

"Stop," he insisted. "Don't just dig in. I gotta run down some shit."

Zoro rolled his eyes grandly, then reached out to take up a knife and fork, holding them and shooting a look Sanji's way. He'd actually been shown how to use them before, at O.H.A.R.A.

" _Yes,_ " Sanji said, in response to the gesture. "But that's not all. You scarf it all down like you usually do, you're gonna kill yourself. And I am _not_ gonna do the fucking Heimlich on you."

Zoro threw his head back and groaned to the ceiling.

" _Everything_ kill humans!" he protested.

"Not if you know what you're doing!" Sanji insisted. "Now listen!"

And then he launched into a long-winded explanation, a lecture that rivaled Robin's, about how to chew food without dying and swallow without dying and how to take small bites without dying. By the end of it, Zoro was ready to fall asleep, but he'd probably die doing _that!_

Admittedly, drinking was fucking weird, and he _did_ almost inhale the liquid, but that was _beside_ the point. He just tried to take Sanji's advice from earlier and didn't think about it, let instinct take over.

It worked too, because before long, he was consuming his meal without problems, and the fact that food actually tasted _amazing,_ when he usually didn't care for cooked stuff, was probably attributed to his human tastebuds. Suddenly, the thought of raw meat wasn't that appealing.

He wasn't going to tell Sanji that the food he'd prepared was good though, so when Sanji glanced up at him and asked, "Well?," Zoro simply shrugged and looked disinterested.

Of course, he had to suppress a smirk when Sanji made a disgruntled noise in response. Clearly, the guy cared a lot about his cooking.

Silence fell over them, Sanji's eyes flicking repeatedly to Zoro practically every time he took a bite, but when it seemed Zoro could handle eating after all, he sighed and set down his fork.

"So I called Dr. Nico, but she didn't pick up," he said. "And as much as I know it's useless to ask you, I wanna know how the hell you got here. How does that bracelet work? Where did you even _get_ it? And furthermore-"

"Stop talking," Zoro complained, wishing he had a more succinct way to make Sanji be quiet in the blond's language, but that phrase would have to do.

Honestly, did Sanji _want_ to be understood when he jabbered on and on like that?

Sanji just growled, then reached out to snatch Zoro's wrist, bringing it across the table so he could examine the bracelet again.

He couldn't see anything particularly _magical-looking_ on the outside, just flat, thin metal, though there was a tiny raised button that he nearly pressed out of curiosity.

" _Don't!"_ Zoro hissed when he tried, yanking his hand back. "Opens it!"

Oh.

"Well, _tell_ me that first!" Sanji shot back, then gestured for his hand again, Zoro scowling but plopping his wrist back into Sanji's waiting palm.

"I really don't understand how _this_ is capable of altering DNA…." he muttered to himself, turning Zoro's wrist around a few more times. "The only way that's possible is at the molecular level, and a _bracelet_ shouldn't-"

"Inside. Two - points-?" Zoro interrupted, and when Sanji looked up in confusion, he brought two fingers up and seemed to mimic fangs.

Sanji blinked at him.

"What?" he replied.

" _Inside,"_ Zoro repeated, pulling back his wrist and tapping the bracelet insistently. "Two points!"

"That clarifies nothing, idiot!" Sanji huffed, but then Zoro grabbed his arm and jammed his two fingers into it sharply, saying, for the third time, "Two points!"

And just for the fun of it, he jabbed him again, several times, until Sanji snarled and shoved his hand away.

"What, like _needles?"_ he hissed, scowling at the many fingernail indentations Zoro had made on his forearm.

"Needles!" Zoro confirmed, actually remembering the word.

"Ugh, so fine, there's two little needle points on the inside?" When Zoro nodded, Sanji just rolled his eyes. "Okay, so that still answers nothing. Is it injecting you with stuff? Is it fusing with your genetic structure? Does it hurt?-"

Zoro opened his mouth, ready to silence him again, but Sanji beat him to it.

"No, don't try and stop me! I will _not_ shut up!"

"Shut up!" Zoro yelped in revelation, now reminded of _two_ useful phrases in one go, and the smug look he shot Sanji was enough to make the blond realize his mistake.

"This is going nowhere," Sanji muttered, shaking his head and sighing. He lifted his fork and pointed it in Zoro's direction. "Here's what's gonna happen. We finish eating, get you in some damn clothes, and then you let me try that thing like you promised."

This actually had Zoro's face lighting up, a grin that couldn't be disguised as anything but excitement tugging at his lips.

He then proceeded to start shoveling food in his mouth even faster, and maybe he _wanted_ Sanji to grab him again, try and keep his fork from his mouth.

Because every time he let go, that gentler slide of Sanji's fingers across his skin actually felt pretty nice.

* * *

 _ **M.A.R.I.N.E.S. Laboratory Headquarters, North Blue**_

* * *

"I'm _so_ sorry, Tashigi! We should have come sooner! We went straight out to check on the seals and-"

"What Coby said! Please don't fire us!"

Desperate pleas from the two men currently working on removing the netting that bound the woman's arms tightly behind her back, Coby smiling apologetically as he pulled off the tape covering her mouth.

Immediately after, Tashigi spit out the old rag balled up in her mouth and coughed a bit.

"Helmeppo," she managed to stutter out. "It's not your fault. You both went home before it even - happened. If anything it's - my fault."

More coughing until she huffed out a breath.

"Can one of you please - get me some water-?"

"Right away," Coby said, the pink-haired man quickly getting to his feet, gesturing for Helmeppo to work on the netting while he hurried from the office.

"Scissors…" Helmeppo muttered to himself upon eyeing the tangled netting.

"Top drawer of my desk," Tashigi said, and he nodded, rummaging for a pair which he brought back over to where the woman still sat inside the closet.

"Where's Captain Smoker?" she asked, blinking at him a few times as her eyes struggled to focus without her glasses.

"Not sure," Helmeppo replied, starting to snip away at the first layer of netting. He lowered his voice, sounding a little guilty. "Think he went to the lab. If he did, bet he'll show up here in a few minutes….what with the specimens missing and all..."

"They're _missing?"_ Tashigi repeated, eyes wide and mouth dropping open in disbelief. Some of her hair flopped into her mouth and she spluttered to spit it out without her hands. "I _knew_ she was up to something!"

"Who?" Helmeppo asked. "Do you know who did this to you?"

"Of course I do!" she replied. "Kuina!"

"Kuina?! What?!" the man yelped. "But - how!"

"I told you! She was up to something!"

"Uh, if she tied you up and stuffed you in the closet overnight, I'd say that's definitely reason to believe she was up to something… But in case you forgot, she's a _mermai-!"_

Running footsteps, and then Coby rushed back into the room with a bottle of water in hand.

"Sorry!" he apologized as he fell to his knees beside the two. "I didn't have the extra ten cents for flavored!"

"Oh, don't worry about it," Tashigi replied, smiling when Coby opened it himself and offered to help her drink since her arms were still tied. "Have you tried the peach though? It's actually pretty tasty!"

"I know! I had it yesterday!"

" _Guys!"_

Tashigi and Coby both turned to look at Helmeppo, who shoved his sunglasses higher on his head with a huff when he had their attention.

"As much as I can appreciate a good flavored water, this is _hardly_ the time to be discussing it!" he insisted. "The specimens are _missing!_ This is a huge problem! And if Dr. Sakazuki finds out-"

"He already did."

The addition of a new voice brought an instant shift in mood, and it was no surprise when the smell of cigar smoke filled the air, a heavy waterproof boot coming into view a second later.

Its owner was Captain Smoker, and his presence was one that commanded respect. He was one of the lead scientists working with the M.A.R.I.N.E.S., but considering the tight ship he ran on missions, the 'captain' moniker had stuck rather steadfastly.

Until a few days prior, he, his assistant, Tashigi, and a small crew had been stationed at a tiny research center, an observatory moored in the middle of the ocean, Grand Line station five, or G-5 for short.

They'd been sent there with the main objective of establishing good relations with the merpeople of Fishman Island, under the guise of studying wave patterns. What had resulted was a rather good relationship with their king, Neptune, and his three sons, who'd been friendly and cooperative on the literal surface.

But that was just it. They'd come up, but never invited any of the humans down. They were secretive. They kept their kingdom protected, and not even the countless submarine missions G-5 employed had uncovered it.

It seemed impossible. An entire _kingdom_ hidden away...

Time had passed, several years, since Tashigi had first come on as a young intern anyway, and the costs of keeping their crew there grew until it had no longer been productive.

And now, here they were, with Tashigi witnessing, for the first time, the surprising conditions here at Headquarters, most surprising the "guests" they'd been harboring for far too long, in her opinion…

Dread seemed to fill the room at Smoker's words, Coby and Helmeppo looking at each other nervously as if it was somehow their fault that the head of the organization had found out.

Helmeppo scrambled aside when Smoker came closer, lowered himself to a knee next to Tashigi and pulled out a rather fearsome-looking knife from inside his boot, which he quickly brandished with a gloved hand and began making quick work of the netting still trapping her.

Before long, he had her entirely freed.

A sigh as Tashigi pushed the netting off herself and gave arms a shake to wake them up.

"I know we look alike, but did Kuina really fool you last night, sir?" she asked, though her tone was more teasing than angry, and she smirked when his cheeks reddened a bit.

"Come on," he said gruffly, getting to his feet without further word on the subject. "We're going after them. Sakazuki already sent a team out."

As soon as he'd said this though, Coby and Helmeppo exchanged another apprehensive glance, something that didn't go unnoticed, the captain slowly quirking a brow at the two of them, particularly when they looked ready to say something.

And indeed, it was only another second before Coby seemed to muster his bravery, pushing his glasses further up on his forehead to say, "C-Can we join you, sir? I don't - think it will end well if Dr. Sakazuki tracks them down first…"

Smoker seemed to regard this request for a while, the silence that followed a little uncomfortable under his scrutinizing gaze.

"He doesn't know where they're headed," he replied simply, as if _he_ did, and the sharp intake of breath Tashigi took from around her bottle of water almost confirmed it.

"The East Blue colony…" she murmured, lowering the drink to her lap. "Do you really think it's where King Neptune said?"

"King Neptune wouldn't show us his own kingdom. I see no reason to trust his word," Smoker replied, turning his back and crossing to the door, kicking aside some of the discarded netting as he went.

"King Neptune…? _The_ King Neptune-?!" Coby cried, scrambling to his feet as soon as Tashigi did, arms outstretched to help her if need be, but his gaze flicking quickly between her and Smoker.

No response to his outburst, Tashigi already on her next thought as she stumbled after her boss.

"How will we track them then?" she asked, giving a yelp when her foot nearly tangled in the net.

"We follow a different set of directions," Smoker replied, already out in the hallway. "From an East Blue ally."

"Sir, with all due respect," she shot back, absentmindedly flipping off lights in the room, even though Coby and Helmeppo were still bringing up the baffled rear.

She lingered in the doorway, lowering her voice as her eyes moved up and down the thankfully empty hallway.

"Why don't we just let them go?" she muttered. "I don't...like the conditions I've seen here….and knowing how long they've been kept here…..it's not….right…."

This seemed to strike a chord with the man, who stopped, his back turned, but his head angling slightly towards her.

"That will depend on how cooperative they are," he replied quietly.

Tashigi's eyes widened.

"What do you mean, sir?" she stammered.

Smoker sighed, pulled the collar of his open jacket up, and started walking again.

"Come on," was all he said. "All of you."

This earned a surprised reaction from Coby and Helmeppo, though they quickly hurried after him.

Tashigi gave a huff, squinted eyes at the blurry surroundings.

"Sir, I don't have my glasses!" she cried, giving a squeak as she nearly tripped over her own feet.

Smoker didn't look back, strides lengthening as he moved swiftly down the bare hallway.

"Tashigi, if you call me 'sir' one more time…" he muttered, then reached into his jacket pocket to pull out the maroon pair, jutting his hand out without looking back. "They were by the outdoor enclosure…"

She gasped, then happily took them, only aware of his scolding a few seconds later.

"I'm sorry, si-Captain," she replied.

A sigh though as she realized the man was indeed heading towards the east wing of the building, where the boat docks were located.

"Do we have permission to take a boat?" she asked, a bit of guilt and apprehension in her voice.

For the first time that morning, Smoker's lips turned up in a smirk.

"We're not asking for permission," he stated.

* * *

Sanji hadn't intended for his guilt to override his desires to try that bracelet. As soon as he'd gotten Zoro back into those wetsuit shorts and a pair of flip-flops, he'd marched him right over to the lab.

He blamed his minimal dressing of the mossball on his excitement over the bracelet. Plus the idiot was clearly more comfortable in next to nothing, and that was why he'd left him shirtless. Out of the _goodness_ of his heart.

But, excitement aside, the farther down the walkway he got, the louder his father's request from his note whispered in the back of his mind.

And by the time he'd scanned the both of them into the rehab room, Sanji had turned around to poke the following merman in the chest, declaring that as soon as he finished logging the slides from the other day, they'd get right in the water.

Of course, this had annoyed Zoro, but he was honestly too preoccupied with trying to walk with the weird rubbery shoes Sanji had given him.

He looked like a stupid duck, trying to walk with those things, legs lifting too high, stumbling about, Sanji thought with amusement.

So, a half hour later, Sanji was parked at a lab bench, hunched over a microscope, setting a tiny algae sample onto a labeled glass slide. He was practiced, but it still took concentration, trying not to smear it too much, placing the plastic seal just so….

He was glad Zoro hadn't distracted him, though he did find himself glancing over his shoulder to the turtle tank before long, where Zoro had draped himself over the edge, brushing fingers over Lettuce's back when she swam close.

He did so gently, and though his own back was mostly turned, Sanji caught a glimpse of a smirk on Zoro's face when Spinach came over to say hello, bumping her head sweetly against his hand.

Sanji folded arms over the back of his chair, found himself watching the scene for longer than he'd intended before he asked, "Can you talk to them?"

Zoro looked over, cheek pressing into his shoulder, raising a brow and pointing at the turtles in question.

"Yeah," Sanji said. "Like can you understand them?"

This time, Zoro pulled a face, a deadpan expression.

"No," he answered flatly. "You talk to - _land_ ones….?"

Sanji opened his mouth, but then closed it, deciding to give the mosshead that one.

"Okay, good point," he conceded before swiveling back around to his work. "I just wondered 'cause you're half fish and all…"

Zoro rolled his eyes, then, with one last tickle of fingers over Spinach's shell, he pushed off the wall and walked over to Sanji, slowly, but with only a few glances at his feet.

"Hey, that was pretty good." The blond grinned when Zoro's form came up beside him. "Didn't hear you trip at all."

A snort from Zoro, who carefully lowered himself onto the chair beside Sanji, straddling it experimentally, then relaxing as he slumped over the backrest.

"Done?" he asked, sounding like a bored child as he eyed whatever the hell Sanji was doing.

But dammit, he'd been at it for far too long, and it wasn't even clear what he was _doing_. He was just looking into that science thing and moving little bits of clear shell around. As far as Zoro could tell, it was pretty pointless, and he was growing pretty impatient to get the blond in the water.

"Not yet," Sanji replied, eyes glued to the microscope again. "But trust me, I'm going as fast as I can."

Zoro huffed, then rolled his chair closer to the table so he could rest an elbow on it.

Things went quiet again, save for the occasional splash of water from the tanks behind them, and Sanji seemed so focused on his work that Zoro was tempted to mess with him. But that would probably slow him down, so there he sat, yawning dramatically a few times to express his ennui.

Eventually, after several minutes of staring at Sanji (and finding he wished he was still wearing the shirt from last night, the one that had showed off his chest), his fingers drifted, reaching out to play with the weird card thing hanging from his neck.

It had his picture on it, and some other writing, including the B.A.R.A.T.I.E. symbol, a stylized open-mouthed fish in simple blue and white. Some kind of identification thing, he figured, if it was like the ones the staff at O.H.A.R.A. wore. More importantly, it was fun to flick, which he set to doing, eventually trying to see if he could get it to flip all the way around Sanji's neck.

Sanji tolerated it for longer than Zoro anticipated, so he kept at it….but after an especially good flick that sent the lanyard flipping up to slap Sanji in the face, the explosion he finally received was incredibly satisfying.

"What the _hell_ , mossball, are you two years old?!" he shrieked, grabbing Zoro's wrist forcefully in a hard squeeze. "You distract me, this is gonna take twice as lon-"

But that was when he realized, with a sudden jolt of dread, that he'd accidentally depressed the button on the bracelet still on Zoro's wrist, feeling it snap open beneath his palm.

He barely had time to utter, " _Shit."_

What happened next was something he'd only ever seen in movies.

Zoro's eyes went wide and they _changed_ , his pupils visibly narrowing, and the irises darkening almost unnaturally until his eyes were no longer human, but undeniably those of a shark.

At the same time, the breath seemed to be stolen from his lungs, expression panicked when he met Sanji's.

The blond just managed to scramble up and catch him as the merman gave a violent twitch and started to slide sideways off his chair, body tilting dangerously towards the concrete floor.

His arms flew up, clinging to Sanji for stability as the man hastily lowered him to the ground, hovering over him fearfully as an equal parts pained and choked grunt left the merman, his body twitching again.

And then, his lower half seemed to go rigid, legs snapping together as his skin started to morph, changing texture and color until it was the green of his shark skin tiling itself up over his legs, fusing them together and even overtaking his shorts.

The shape of them lengthened, fins pushed their way out from stretched skin, almost grotesquely, and the rolling chair clattered into the table as Zoro's fully-formed tail sprouted out and hit it, far longer than his legs had been.

And by the time Zoro finally relaxed, or rather, went a little limp, in Sanji's arms, he was his full mer-self again. Gills and all.

Sanji couldn't move for a second, still shocked after witnessing a full-blown CGI transformation _in real life._

That is, until he felt Zoro shift, fumble for his hand, which still held onto the bracelet.

"Back…..on…." he stuttered out, and only then did Sanji snap out of it.

"I'm sorry! Fuck, I'm sorry!" he hissed, hastily grabbing Zoro's wrist and practically slamming the bracelet around it.

This time, the same transformation, only backwards, human skin overtaking his shortening tail, the appendage splitting in half to leave him with two green tentacles for a moment before they began to mold into leg shapes.

Fins smushed back down into his body, and though Sanji couldn't see his eyes change, Zoro having squeezed them shut this time, the metamorphosis did reach his upper body, judging by his loud gasp a second later.

A few coughs and wheezes, but he was human again, and clad in his shorts, oddly. This bore the question of why clothing items weren't affected. Hardly the time though when Sanji had Zoro flopped there on the floor, still panting after the ordeal.

"Are you okay?" Sanji asked, a hand on his chest as he leaned in closer.

Zoro didn't open his eyes yet, just nodded up at the ceiling, concentrating on his breaths by the looks of it.

Sanji too gave a huff and sat back a little, leaving his hand where it was.

The whole thing had freaked him out, probably because of how unexpected it had been. It had hardly been the amazing, magical transformation he'd expected. In fact, it had almost seemed to cause Zoro pain, though that could have been because it had happened at the entirely wrong place.

Still, it left him with more than a few apprehensions about trying it for himself, even if he desperately wanted the end result.

Not for the first time, Sanji had a moment, a moment where he realized just how insane all of this was. A self-aware moment that reminded him he had a _merman_ here, and he'd just witnessed something straight out of fantasy occur right before his eyes.

He felt Zoro calm, felt his breaths begin to even out, and the rapid pace of his heart slow beneath his palm.

By the time Zoro opened his eyes, Sanji's hand had trailed off his chest, down to that bracelet again, which he brushed fingertips over delicately.

The blond was quiet, and he didn't look ready to get up, judging by his furrowed brow, the way he'd propped up a knee to rest his other arm on it.

"I don't get it, Zoro," he murmured, not looking up as his fingers moved to touch the merman's.

Zoro didn't stop him.

"Why would my dad keep all this from me?" Sanji continued, unsure why he was being so bold, lifting Zoro's hand so he could press their palms together and lace fingers absently. "About all of you, I mean. He's not the most open guy, but this is _huge_ ….and I'm his _son._ He knows he can trust me."

Zoro didn't know what Sanji was doing with their hands, but he went along with it, letting him play gently because it felt pretty nice for some reason. Probably some weird human thing though.

"Keep you safe," Zoro replied with a shrug because why should it be any more complicated than that?

"But from what?" Sanji sighed, shifting his hand slowly down from Zoro's hand to his forearm. "I'm starting to wonder if _he's_ secretly a merman…"

The merman gave a snort, obnoxious enough that Sanji finally looked at him properly and narrowed eyes.

"No," was all Zoro said, smirking as he pushed himself up to a sitting position.

This brought him close to Sanji's face, and the blond found himself at a loss for words, annoyingly enough. All he could do to express his irritation was glare at the idiot.

Of course, that glare melted a second later when, suddenly, Zoro's fingers found his hair, curiously threading through the curtain that covered his right eye.

Sanji let him, watching to see what he would do. There was nothing wrong with his other eye. In fact, he used to keep it uncovered. But he had to admit, it was a little bit of self-consciousness about his eyebrows that-

"Two. Questions," Zoro said, punctuating both words with a poke to each of Sanji's eyebrows.

" _Dammit, mosshead!"_ Sanji shrieked, wishing Zoro was wearing a shirt to grab, but instead settled for shoving him hard. "Would you drop it already? _Yes,_ I know, okay? They're weird! As if I didn't get enough shit for it growing up!"

Zoro laughed, and Sanji tried hard to deny the fact that it was pretty fucking cute. Zoro was an irritating lout! He wasn't allowed to have cute qualities!

"Not only one," Zoro snickered, letting Sanji's hair fall back over his face, which went red in response.

"I said I _know!"_ Sanji hissed, and he reached up to push the merman again, harder this time. "How 'bout I go off on your stupid hair, huh-?"

" _No._ Mean - other ones - have," Zoro interrupted, taking both of Sanji's wrists in his, first to stop another incoming shove, but also to distract him, particularly when he grinned and laced their fingers.

It worked, though Sanji looked torn between being distracted by his hands or his words.

"You know….someone with eyebrows like me….?" Sanji muttered quietly, a puzzled frown on his face, eyes fixed on Zoro's hands pressing against his lightly.

Zoro nodded, leaning his weight onto Sanji's hands teasingly.

"You're not special," he said, watching the blond, who was now studying his lips quite obviously.

"Yeah, well…." Sanji breathed, and Zoro's grin was broadening before he'd said anything else.

"Neither are you," the blond finished unconvincingly.

Zoro didn't believe him at all.

* * *

 _ **North Blue, en route to East Blue**_

* * *

The ocean was warm, and despite being the same water that sloshed over the breakers, filled the outdoor enclosure at the M.A.R.I.N.E.S. headquarters, it felt incredibly different.

There were things she remembered distinctly about the open ocean.

She remembered that feeling of swimming as fast as she could, bursting through a school of fish just for the hell of it, because it was fun to watch them scatter, and it was fun to see Zoro get slapped in the face by their flailing tails. She'd always been faster than him.

She remembered the towering reefs that made her seem small, remembered hunting for sea urchins there, how she could tell exactly where the grumpy eels lived by the bubbles that would float up from certain holes.

She remembered the first time she thought she'd lost Zoro for good, when they'd dared to swim out into open ocean in search of that school of marlin that had been circling the settlement for a few days. There had been nothing around them, nothing in sight but each other, and Zoro had _still_ managed to swim off. She'd found him hours later in a seaweed forest, crankily claiming _she_ was the one who'd gotten lost.

She remembered the last time she'd lost Zoro. Fifteen years ago now.

The time that had _really_ been for good.

That was why the ocean felt so different.

She was free, but it was empty.

"Kuina…..Hey….. _Woman_."

She looked over finally, tearing her gaze from the deep undersea chasm that stretched far above and far below them, instead focusing on the merman perched beside her, lounging casually on the rocky ledge.

"What the hell's wrong with _you?_ " Ichiji asked, pulling down his sunglasses to shoot her a look from behind his long flop of red hair that always managed to conceal half his face despite being underwater.

Kuina watched him for a second, knew that this was his snarky way of showing concern, even if none of them were particularly good at expressing their feelings.

"Nothing," she said with a shrug. "I'm great."

And to prove it, she ignored him once more, turning her attention back to Niji and Yonji in the distance, the two still tearing into the tornado of herring they'd herded into the chasm.

Sunlight filtered through the clear water in bright diagonal columns that illuminated the fishes' scales, the mermen's laughs and growls echoing out as they toyed with their prey.

"Surprised your crazy plan actually worked," Ichiji mused, snorting when they saw Niji chomp through two fish at once with a triumphant fistpump. Kuina knew Zoro had been able to take out five, as a young child.

Crazy plan…..

It had been the _only_ plan, upon meeting that Tashigi woman, who'd been transferred in with the group of scientists from G-5.

Everyone had marveled at how similar they looked, and it had pissed Kuina off enough to make it work to her advantage, especially when Tashigi had turned out to be far too kind and maybe a little naive.

All it had taken was a simple, sincere request to try that bracelet the M.A.R.I.N.E.S. harbored, a headbutt to knock the woman out once she'd figured out exactly where she needed to go to open the water filter ducts, and the rest was history.

She'd lucked out entirely, even benefiting from Tashigi's clumsy nature as any walking difficulty that occurred while she was disguised could be easily explained away.

"You still underestimate me…..and it's damn annoying," Kuina muttered.

"I have pride," Ichiji sneered, and though his tone was teasing, Kuina knew better. He meant it. She supposed a lifetime of being told he and his brothers were _special_ didn't help their egos at all.

"We need to keep going," was all she said. "We linger any longer and the ships will catch up to us. Go round up those idiots."

Ichiji scoffed, his long red caudal fin flicking a stream of bubbles her way.

"We're back in _our_ territory now," he replied. "You need to start respecting royalty, woman~"

This irritated her even more, because the royalty she'd been training so hard to protect all those years ago was _not_ what Ichiji and his brothers had turned into.

The Princess had been kind. Strict, and a little aloof, but strong, and worthy of the title.

Kuina knew, deep down, that what these three had grown into had simply been a way to cope, their arrogance, their cockiness. _Anything_ to combat the horrible loneliness and isolation. Anything to make them feel like they were more. More than just experiments. More than just something to study.

Unlike her, they'd never known any different.

That still didn't excuse their attitudes, and as she'd always done, even with a self-assured little merboy who'd been certain he could beat her at everything, all those years ago, she wasn't afraid to squash that hope.

"You don't stand a chance without me," she reminded, tone biting. "You never even learned our language."

"You can't act like you remember all of it! You've nearly lost it entirely!" Ichiji shot back, scowling.

"At least I spent eleven years of my life down here!" she growled, glaring at him. "You spent none! You. Know. Nothing."

But despite her anger, Ichiji's scowl simmered into a smirk, and he gave a carefree shrug.

"Lighten up~" he replied smoothly. "Maybe I was teasing."

A smirk and he swished his tail around to brush the tip against her cheek.

"You're cute when you're bitching, y'know~"

She jerked her head away, almost wishing she could relax as much as Ichiji and his brothers. But she was the conductor here. Yes, they had formulated the escape plan together, but getting them to safety was on her right now.

They were relying on _her_ foggy directional memory, _her_ potentially shoddy translation skills, instincts that had dulled after such a long time living at the lab.

And there was still no telling what they'd find if they _did_ make it back to the settlement….

"So I've been told," she muttered, deciding to remain serious. "Until we're far away in East Blue, I'm not in the mood for your stupid sense of humor. Now _go round up your idiot brothers._ I'm not gonna say it again."

Ichiji didn't move, just continued floating there comfortably on his back, though he did seem to consider her words for a moment before he simply grinned.

"Princes don't take orders from commoners-"

"They will if the commoner can kick their ass!" Kuina quickly countered.

She drew her fist back then, made to punch him, and that was finally what got him up, the merman chuckling as he flipped himself out of the way and swam off towards his brothers with one last touch of his tail to her jaw.

Kuina watched him go, then sighed and shrugged off the backpack she wore, unzipping it to check over everything she'd brought. The packing had been a little hasty, but they didn't need much, just some extra netting, and a few knives she'd snagged from one of the feeding rooms she'd found during her short bout as a human.

Of course, the _most_ important tool nearly floated its way out of the big pocket into open water, so she took the bracelet, unzipped one of the smaller front pockets and shoved it in.

She didn't want to be human. Even if some humans seemed kind, they weren't to be trusted. They'd stolen her identity, her past, her culture…..her best friend.

She shrugged the backpack onto her shoulders again, gray tail giving a swish to get her upright as the brothers began to come back her way, Niji and Yonji complaining about their fun getting cut short.

"I'm sorry, Zoro," she found herself murmuring aloud before she was really aware of it. "We're finally free, but there was nothing I could do for you…"

It wasn't enough. It would never be enough. But it would have to do.

They had to keep moving.

* * *

" _Shit_ , okay - okay. _Zoro_ , don't look at me like that. There's a fucking lot going on right now and it's overwhelming. Fuck."

In reality, there was nothing happening in that moment. Zoro and Sanji were both seated on the edge of the dock outside B.A.R.A.T.I.E., right where Sanji had first discovered the flailing merman the previous evening. He'd finished his work inside, and he'd whisked Zoro out as soon as he did.

They both dangled legs over the edge of the dock into the lapping water below, the heat of the sun on their backs as it climbed higher in the sky.

Aside from a few cawing seagulls, it was quiet and calm, and Zoro hadn't said a word since they'd settled down by the water.

And yet, Sanji had been talking to himself for a full minute. Zoro didn't understand half of what he was saying, but he'd judged the idiot was trying to hype himself up for his bracelet experiment.

"You're _sure_ it will work?" Sanji asked him, almost imploring with his eyes that Zoro answer in the affirmative.

"Probably," the mosshead mumbled with a nonchalant shrug.

Sanji made a weird-ass noise at that, something between a seal's growl and a pelican's call, Zoro thought. It certainly wasn't a pleased sound.

"'Probably' means there's a possibility it won't," the blond grumbled, gripping the wood of the dock and glaring down at the water for a moment of silence.

But then he let out a huff and whacked at Zoro's arm insistently.

"What if I get stuck halfway through! What if - I lose my lungs, but the gills don't form - what if - what if I don't turn into a merperson at all!" he stammered, sounding more and more panicked with each terrifying scenario. "What if I turn into a shitty frog or some shit! What if I forget I'm human and I forget how to talk - I forget who I am or-!"

The instant Sanji felt a hand on the back of his head, shoving him forcibly towards the water, he was ready, lashing out with a sandaled foot to kick Zoro hard in the chest.

"Back off, mosshead, this is serious!" he yelped.

The merman rolled his eyes, then grabbed Sanji by the shirt collar, jostling him to get his full attention.

Once he did, he breathed in and out slowly, almost in demonstration for the huffing blond.

"Breathe, Question," he said softly, mockingly.

Sanji scowled, looked personally offended by that command.

"Shut up, like you can school me on being human," he muttered, flicking Zoro on the side of the head for good measure.

But he did take a deep breath, because honestly, it was now or never. And he supposed, in the end, he'd rather be transformed into a frog than live his whole life not knowing the result.

"Alright, just - take it off first," Sanji said, barely managing to catch Zoro's foot when the merman made to kick his pair of flip-flops off into the sea.

A brief squabble, Zoro pulling off one of his shoes and trying to slap Sanji in the face with it for a minute before, ultimately, he slipped into the water.

Sanji kept a firm hold on him, making sure he didn't slip under prematurely, even though Zoro pulled off the bracelet immediately and plopped it onto the dock beside Sanji.

This time, there was a tiny bit of discomfort on Zoro's face when the changes jerked his body, but it seemed to be far less painful because, before long, a sharp-toothed grin spread over Zoro's face, and he pulled away from Sanji's grasp to float onto his back, newly-returned tail purposefully splashing water into Sanji's eyes.

He ducked his head under to wet his hair, then folded arms behind his head and watched the blond expectantly.

"Did it hurt…?" Sanji asked, a little fearfully, but Zoro shook his head.

"No," he replied. Not here, in the water, where he wouldn't fucking suffocate. "Feels….warm…?"

He didn't have the words, even in his own language, to describe the exact feeling, that slow heat spreading through him, the strange sensation of his body molding itself back into its true shape.

Sanji just had to try it for himself.

And he was going to, a look of conviction coming across his face. He stripped off his shirt and lanyard, folded the top neatly, and set them aside. Shoes and shorts followed until he was down to his wetsuit bottom as well, with nothing left to do but get in the water.

He did, sliding in tentatively, still clinging to the dock.

"Should I - go underwater or…?" he mumbled, unsure of how to go about this.

Again, Zoro simply shrugged, the picture of disinterest. But his eyes were focused, almost curious, and Sanji had to wonder if the merman was really anticipating this as much as he was.

"You're so helpful, Zoro," he huffed, fingers hovering anxiously over the bracelet before finally picking it up.

Worst case scenario.

Worst case scenario, he became a plankton. He'd be dead in a day, and he'd have to trust this idiot fish-man to pass on his hard-earned legacy. In the end, all his hopes and dreams would be dashed, but at least the world would be a better place for science, right? All because he'd taken one for the team and sacrificed himself with bravery.

So long, world, in that case.

"Fuck, well, here goes nothing…" he said, took a deep breath, possibly his last, and ducked under the water, snapping the bracelet onto his wrist.

He felt the slight sting of two tiny pricks into the skin of his wrist.

A moment of nothing.

And then, his body jolted, the breath he'd been holding rushing out of him in a stream of bubbles.

His first thought was to panic, but he couldn't move as a coiling warmth seemed to wrap around his entire body, almost dragging him deeper underwater.

He tried to kick legs….

Except they'd locked, and he couldn't even _feel_ them anymore, numb, save for the sensation of ants crawling over his skin, all the way up to his torso, even over his face.

It should have freaked him out, especially because he couldn't breathe and-

Suddenly, the ache in Sanji's lungs was gone, and in fact, much like his legs, there was no feeling there at all, at least none that he was used to.

Yet he felt perfectly normal, and he realized it was because of the flow of water entering his body close to where his hips should be, the soothing rush of oxygen flooding him just as it would if he took a deep breath.

Except….he was….underwater….

His heartbeat thundered in his ears, and then, he heard Zoro make a disbelieving noise.

When he opened his eyes, Zoro was crisp and in focus, hovering there in the water opposite him, having come under at some point too, the dopiest, most amazed smile on his face. And he was staring at Sanji's lower half….

Very slowly, Sanji shifted his gaze downward.

There, _attached_ to his torso, just like Zoro's, was a brilliant tail of a surprisingly saturated blue, the skin of his abs morphing seamlessly into skin that was much smoother and softer.

He himself made a noise that was a little embarrassing in his shock, high-pitched as it was, but fuck if he cared about that when he gave a spin and found a full set of fins, dorsal, pectoral, and an overly long caudal that twirled like a ribbon with his movement.

He wasn't a frog. He wasn't a plankton. He was a fucking thresher shark, he recognized immediately, albeit one with far more unique coloring than he'd ever seen in the wild.

Eyes, unbothered by the salt water, flicked to Zoro again, and this time, when they did, something strange overcame him. Zoro was still staring at him, almost in awe, and even if he was still just a _little_ bulkier, the urge was there because he was wide open.

And the next thing he knew, Sanji had darted forward in the water easily with a flick of his tail.

He shot forward, reached out a hand and grabbed Zoro by the throat in a grip that was suddenly iron and unbreakable, slamming him into the dock support behind them and holding him there, baring sharp, pointed teeth in a show of dominance that he certainly hadn't been planning.

His body just moved on its own, and it was as if he had never been human, the instincts so powerful and so natural.

Amazingly, Zoro, who normally looked like he could bend a car with his bare hands, didn't do anything. He didn't fight back. He didn't try and free himself.

He simply hung there in the water under Sanji's grasp, until the blond's eyes came back to some sort of clarity, and it was _Zoro_ there and not an ambiguous threat to - to _what_ even? Why was he doing this?

He released Zoro quickly, looking away almost sheepishly in shock that he would even do such a thing.

The hand that had grabbed Zoro shook slightly when he held it out before him, so he clamped it down on his opposite forearm, unable to keep his gaze from his tail for too long.

"Why...did I do that…?" he muttered, and to add to the oddities, he found his voice to be perfectly clear and audible, sounding to him just as it would above the surface.

Zoro didn't answer him though, just kept right on staring at him, seemingly unfazed by his sudden show of aggression.

"It - you - changed-" Zoro stuttered out, and Sanji couldn't help but roll his eyes at Zoro's unhelpful answer.

"Yeah, I got that much, idiot. But why did I-?"

"It - _worked!"_ Zoro exclaimed, interrupting him. "You're really - really-!"

"Zoro! We fucking know! Get your goldfish mind focused, come on!" he growled, snapping fingers to catch Zoro's attention, creating a stream of bubbles between them. "I'm asking you why-"

Zoro's arm shot out, his hand grabbing Sanji's wrist and lifting it to shove the bracelet in his face.

" _This -_ only - changes-" He shook his head and corrected his words. "Works - for _merpeople_ ," he said smugly, with a broadening grin. "Means it's true."

Sanji's eyes widened, his heart doing a flip in his chest.

His mouth gaped for a long moment, trying to form words that wouldn't come before he finally forced himself to stutter out, " _What?,"_ wondering if he'd even understood the merman right.

"But I'm not-" he said weakly after another moment, even as Zoro released his wrist and backed off, crossing arms over his chest, still with that grin on his face.

"Dr. Red - _not_ your dad, yes? _Real_ dad?"

Sanji shook his head silently, bewildered.

Zoro nodded resolutely.

"Before-Queen saved you. From M.A.R.I.N.E.S.," he said matter-of-factly, but when Sanji couldn't reply to that either, Zoro shot him a look of growing annoyance.

"Your _mom?"_

No response.

Zoro scoffed, then, similar to Sanji's attempts at getting through on the boat to O.H.A.R.A., tried, " _Mother?"_

Nothing.

Zoro groaned, mumbled a few curses in his own language, then grabbed Sanji's wrist again and tugged his shocked form forward in the water.

"Let's go to palace," he growled, figuring he'd broken the idiot anyway, who trailed limply after him with a dumbstruck expression on his face.

Better to let the Queen explain. If he didn't shock her as well by showing up with her long-lost brother….


	7. Noah

"This is insane! _You're_ insane! What the hell do you _mean_ I'm a merman?!" Sanji shrieked, prying himself from Zoro's grasp and swimming up beside him. "I'm a _human!_ I've always been a human! I've been to the doctor my whole fucking life and nothing has ever…...Holy _shit..._ Hold that thought..."

He trailed off as, suddenly, the sandy bottom some twenty feet below them began to slope dramatically downward, revealing the large expanse of colorful reefs that Sanji had dove in countless times. But there was something about this absolute freedom, his body completely uninhibited by bulky, heavy scuba equipment, that had him see things in an entirely new light.

An experimental flick of his tail, and he found he could dive down deep in a matter of seconds, no pressure on his ears or chest. The extreme length of his caudal fin should have been a nuisance, but he could control it perfectly, aware of every ripple and turn it gave.

It was now crystal clear how thresher sharks were able to use their tails as deadly weapons. It was almost like having a powerful blade on the end of his tail, and there was something satisfying about that when comparing it to Zoro's shorter fins.

He coasted smoothly through the water, parting little groups of tropical fish as he went, stopping by a particularly vibrant patch of anemones that he'd never been able to see this close in the wild before. Not without cumbersome goggles and oxygen hoses in his way.

Not to mention, it almost seemed that, unlike in his human form, fish were attracted to him. He rolled over with a grin to discover some clownfish hovering close, poking gently at his tail with their tiny mouths.

He smiled, lifting a finger slowly, and chuckled when a few swam over to examine his hand.

"Hey there," he murmured, and despite what Zoro had said earlier, he asked, "Can you guys understand me…?"

No indication that they could, none of them suddenly snapping to attention like an animated movie, and certainly none talking back.

"Said before. Can't talk."

Sanji looked up, through the cloud of patterns and colors that had surrounded him, to see Zoro floating a few feet away, arms crossed over his chest. And also entirely fish-free.

Sanji wondered, a little smugly, if the little things were only attracted to _him_.

"It was worth a shot," Sanji replied with a shrug.

Zoro swam a bit closer, and the blond's new friends scattered, bringing a pout to Sanji's lips. Theory confirmed. Zoro repelled all forms of life.

Instead, Sanji leaned back, feeling his bare shoulders bump against the pink coral behind him, and he decided to close his eyes, concentrate on the feeling of his body lifting and falling gently with the movement of the water.

It was an amazing feeling, being completely free of any burden, even _breathing_ , underwater. This was everything he'd always dreamed about, wanted to experience on those sunny days when the desire to stay underwater and explore forever was strong…..

He'd never been a merman, but he was one now, and it was a dangerous sentiment...the ever-growing thought that he wanted to stay like this…

"Why not believe me-?"

Zoro's voice interrupted, and Sanji cracked an eye open with some annoyance at the disturbance of his peaceful moment.

Of course the green irritant was still going on about his fabricated story.

"Because, Zoro, it's not possible," he stated. "Yes, I can swim well. Yes, I can hold my breath for a while. But my default form is human. I could only change into a merperson _with_ the bracelet, so-"

"But only changes merpeople!" Zoro insisted.

"Fine, well then, maybe I'm the one human exception!" Sanji grumbled. "Besides, if it was true, why wait until now to tell me? Not that I would've believed you before either…."

"Wanted to - make sure _was_ true!" Zoro growled back with growing irritation. This was not the fucking time for Sanji's stubbornness, but the idiot seemed dead set on denying him at every turn.

"You - your dad - before-King making - made - bracelets because - M.A.R.I.N.E.S. but - M.A.R.I.N.E.S. wanted - wanted - _urgh!"_

Zoro cut himself off, not even close to having the vocabulary necessary to describe exactly what he knew the story to be.

" _Queen_ tell you! Your _sister!"_ he bit out, then groaned when Sanji shot him a disbelieving look.

"Okay, so on top of everything, I'm _royalty?"_ Sanji replied in a scathing tone, and he flicked his tail around to whack Zoro scoldingly in the face. "Come on, mosshead."

"Agh!" Zoro screeched in frustration.

He shot out a hand to grab Sanji by the tail, tug him towards him in the water.

Of course, pulling him backwards caused a surge of water to flood his gills in the wrong direction, and suddenly, the sensation of drowning, choking. A thrash of his tail, and he was free, flipping himself quickly and barreling head-on into the other merman with a furious snarl.

Zoro caught him, wrestling him back, then swiping his own tail around for a powerful hit to Sanji's side.

The blond was entirely new to this, and thus had none of the fighting finesse of a true warrior. Even if he and the Queen shared a species, Zoro knew Sanji would have none of her skill.

He was surprisingly strong though, for such a scrawny guy, Zoro found when the hard pounding of his side merely made Sanji growl and come at Zoro again, this time with a vengeance.

It was obvious he was trying to gain some control over the tip of his tail when he swung it back, an attempt to take advantage of its length and sharpness with an attack.

But Zoro was quick. The Queen could whip and cut precisely with her tail like one of those sharp human knives. Sanji was slower, sloppier, and Zoro couldn't help but grin when he over-swung and went spinning about in a circle instead of landing any sort of hit.

"Bad," Zoro said, catching Sanji's fist easily when the blond lunged at him with a punch instead. "Train first. _Then_ try."

"You _asshole,"_ Sanji growled back, unsure of how he'd managed to pin Zoro the first time. Instinct had unexpectedly taken over, but now he was thinking far too hard, and he couldn't coordinate new muscles.

This frustrated him to _no_ end when all he wanted to do was wipe that smug look right off Zoro's face.

Zoro flashed his teeth though and that was a reminder that he had another weapon, a sharp one by the feel of it, as he subtly ran his tongue over now-jagged incisors.

He pushed against Zoro's weight, shoving him back with all his might. He shut his mind off and let instinct rule once more, his body moving of its own accord, jaws opening to bite down hard onto Zoro's shoulder, teeth sinking into skin until he tasted blood.

Sanji had never bitten a person before, never imagined that the sensation would be satisfying in any way, especially not breaking the skin.

But that coppery taste on his tongue was oddly invigorating, and while he stopped himself from gnawing Zoro to pieces, there was still a bit of a manic grin on his face when he pulled away.

His grin fell a little though when he saw the look on Zoro's face, that shocked expression, his eyes entirely wide, and a bright blush flooding his cheeks.

Sanji's heart thumped hard because it was endearing as fuck, but he didn't understand why...

Just as quickly, Zoro's hand clamped onto his jaw, and he found himself slammed back against the rough wall of coral, eliciting a pained grunt, his eyes squeezing shut against the stars that burst over his vision for a moment.

Except he could feel. Zoro wasn't moving away, his body flush with his, pushing him up against that surface.

When Sanji opened his eyes, Zoro's face was close, and there was something in his gaze, something hungry, vulnerable, barely in control. His hand on Sanji's skin shook, and Sanji could feel his heart pounding hard against his own chest.

His lips were so close….

" _Oh, gross! Zoro, get a room! That is so not cute!"_

A piercing female voice, familiar, screeching in his own language, drew a low growl from Zoro's throat, the merman forcing himself to let go of Sanji and shoot straight through the water to grab Perona by the stupid skull T-shirt.

Where the hell had she even come from anyway?

" _It's not what it looks like!"_ Zoro rumbled immediately, despite the trembles that still wracked his body, the heat that coiled within him, and the blood from Sanji's bite trailing off him in thin wisps.

" _What the hell do you mean it's not what it looks like!"_ Perona protested, the mermaid doing her best to shove Zoro away from her, settling for slapping at his chest when her strength couldn't hope to match his. " _I saw it happen! And you've got the mating bite to prove i-!"_

" _I told you it's not! He's-!"_

"Hey! Perona! Remember me? Check it out! I almost gnawed Zoro's head off!"

Dread filled Zoro's gut as the idiot in question swam over with a stupidly cheerful wave, a proud grin on his face.

Perona's jaw dropped, finally seeing a clear view of just _who_ had engaged in such shamelessly open foreplay with the mosshead.

"You?!" she squawked, eyes flicking frantically between the two of them. "But - _how?!"_

Eyes drifted though, until they locked onto the bracelet encircling Sanji's raised wrist.

She made a disbelieving squeak, stared for a long moment.

Then she gave a pump of tentacles and flew at Zoro with the very determined intent to _sting_.

" _ **That's**_ _where you've been?! You disappear for days to screw_ _ **him**_ _?!"_

" _I'm not_ _ **screwing**_ _him, dammit!_ _ **Robin**_ _gave me the bracelet!"_ Zoro hissed, wincing when one of her barbs bit into his arm, but just as determined to argue back. " _She said it was okay! I wanted proof that he's really-!"_

" _So what?! I hope the Queen kills you!"_ Perona growled, now trying to corner Zoro against the coral. " _You know she doesn't want those bracelets in the kingdom! You know what they remind her of!"_

" _Yeah! Her lost family!"_ Zoro screeched back, dodging tentacles left and right now. _"But guess what! One of 'em's still alive, and he's right fuckin' here! I needed proof and I_ _ **got**_ _it, so why the fuck shouldn't he know the truth!"_

" _Urgh, Zoro! Who even says we can trust hi-?!"_

"Um. Alright, so….anyone wanna fill me in on the problem here?" Sanji interrupted, holding up hands and floating up slowly beside the two, turning his best charming grin on Perona, mostly to avoid her sting as well.

She turned to glare at him, cheeks puffed out in a pout, and before anyone could stop her, she'd redirected her wrath onto the blond, swimming right up in his face.

" _You're_ the problem!" she cried, switching languages so Sanji could fully understand her fury. "You were never supposed to come here! Queen Sora wanted you to stay with the humans because you _are_ human! She changed you to _save_ you, and now you're just gonna throw all that away and endanger us anyway by bringing your _human_ friends to look for you probably! Ugh! Just because you're the Prince doesn't mean-"

"Whoa, whoa, wait," Sanji said, searching Perona's narrowed eyes for any sign that she was joking. That she was going along with Zoro's little game that he was actually some kind of mer-royalty.

She was fuming. And Sanji could tell after a drawn-out silence that she was dead serious.

He didn't know why, but the gravity of that struck him even more than when Zoro said it, actually made him wonder, for the first time, if there really was some lost history here that he had no idea about. Something….else his father had been keeping from him?

He felt his heart skip a beat, and his expression must have changed, because hers grew almost confused after a second.

Perona backed up ever so slightly, looking like she was trying to stay mad, but wasn't sure what to do when Sanji suddenly looked so stricken.

"You're…." Sanji stammered quietly, and Zoro seemed to recognize the change in his demeanor too, his eyes fixed on Sanji intensely.

They were serious. They were serious, weren't they.

"But…...how…?" Sanji stuttered out, voice nearly a whisper had he been a human. Which he apparently wasn't, or at least, not in the way he'd thought, as he was starting to realize. "I don't - how is it possible….?"

Perona didn't have a reply for a few moments, looking away, so Zoro swam closer, his voice softer, but no less assertive.

" _They deserve a chance,"_ he said to Perona. " _If the Queen doesn't want to see him, then that's that. But I trust him, and I'll be the one to kill him if he tries to pull anything."_

Perona sized him up, looked to Sanji then, whose gaze was focused on the empty space between them, his brow furrowed.

Her eyes flicked to the bite on Zoro's shoulder.

She cringed, then gave a dramatic groan.

"Ugh, you're both so stupid!" she complained, throwing up arms, jabbing a finger at Sanji a second later. "I'm not calling you 'Your Highness' until you prove yourself, got it! Now come on. _I'll_ get us to the palace."

With a haughty flick of her hair, she jetted herself off, arms crossed over her chest, mumbling about dumb, impulsive, gross, annoying mermen all the while.

Zoro rolled his eyes, the only one understanding her, but he took that fleeting moment of privacy to brush fingers over the teeth marks in his skin.

Sanji didn't know. He didn't know what it meant, and he didn't know the things it had done to Zoro, awakened within him….. Did he?

Still, he found himself reaching out to nudge knuckles gently against Sanji's arm, meeting his gaze when apprehensive blue eyes finally lifted to his.

Zoro quirked a brow, almost in challenge.

"Trust me…?" he murmured.

Sanji stared back, eventually nodding.

"Unfortunately," he said, a tiny smirk coming to his lips.

Then he grabbed Zoro's shoulders and forcibly steered him after Perona.

* * *

Cell service wasn't easy to come by out on the open sea, but that was the way Zeff liked it. Even if it made him harder to contact when he and his crew were out, he could make do just fine with the boat's radio. And honestly, with the events that had occurred within the last few days, he'd rather lose himself again, forget that all of this business had come flooding back to finally affect his son.

The boy was curious, far too curious, and though it worried him, there was no way he would ever assume the truth. He would never assume it, and those who knew would never tell. After all, there was the pact to consider, and so far, the M.A.R.I.N.E.S. hadn't broken their word.

They hadn't gone after the colony again, hadn't done any outward harm, not since that foolish young mergirl had tried to attack one of their research vessels and been captured for it. He hadn't known that her friend, the merboy O.H.A.R.A. had rescued, was the same merman they'd fished up just the other day.

Zeff had been fearful that time. He'd taken Sanji, only ten years old, on a trip inland, taken him to the new science museum that had just opened in the city, let O.H.A.R.A. handle the mergirl's capture, and protected the little eggplant until it blew over.

Her fate was regrettable, but he was not going to see the same happen to the brat he'd grown so fond of, _his_ brat who shared his hopes and dreams in a way not even many adults did these days.

Sanji was a perfectly normal _human_. Despite his heritage, there was nothing worth studying about the boy. He'd never expected to feel so protective over him, considering his reluctance to take him in. But he never could say no to his mother, could he…

Patty and Carne were out on the deck, slacking off by the looks of it, both leaning up against the railing, chatting away as Zeff piloted the boat back towards the research center.

It hadn't been nearly as productive without his son, and in his absence, it was obvious just how much the boy knew to do innately, setting out the diving equipment, securing the coolers, finding the right logbooks.

Why his son had slept in so late that morning, Zeff didn't know. He could only assume he was hungover, and the only reason Zeff had been tolerant was because the boy didn't get out much. He hardly ever saw his friends, and Zeff supposed he could cut him a little slack just this once.

It was quiet as he drove, save for the hum of the engine and the radio playing oldies softly in the corner of the cabin.

That was why he was, admittedly, surprised to hear his phone ring, long forgotten in his back pocket.

They were probably within cell range now that the coast was in sight, but that didn't stop him from grumbling and wrenching the phone out with a little more annoyance than was warranted.

Except it _was_ warranted because, while he didn't recognize the number, he recognized the area code. And only one place called him within that area code.

The M.A.R.I.N.E.S.

A frown on his face, he picked up.

"B.A.R.A.T.I.E. Zeff Red speaking," he muttered into the phone, not liking how soon this call was coming in after his son's discovery of the merworld.

A familiarly gruff voice he'd never expected to hear, especially not after so many years, replied.

 _"Dr. Red. Smoker here. It's been a while."_

Zeff's surprise at hearing from his former intern came in the form of a subtle upwards jerk of eyebrows before they settled low again.

"It certainly has," he said. "There a reason you're callin' from a North Blue number? Thought you were still out on the Grand Line."

" _Tashigi and I got moved back to HQ a few days ago. Don't suppose you heard what's happening over here? The princes and the mermaid escaped."_

Zeff's frown deepened, and slowly, he set the boat on autopilot so he could cross the cabin and close the door.

Patty and Carne noticed, shooting him a questioning look, but he didn't care, just turned back to stand behind the wheel again.

"And what's the plan of action?" he asked, still lowering his voice, even though he'd made it significantly more difficult for his companions to overhear. It didn't matter how it had happened. That was the business of the M.A.R.I.N.E.S.

" _Sakazuki's sent a crew out already,"_ Smoker explained. _"But we're looking to beat them to it. Tashigi's with me. And you know where their colony is-"_

"I don't want any part in this, kid," Zeff grumbled. "I swore off that foolish obsession long ago. You won't get that information from me."

 _"I had a feeling you'd say that_ ," Smoker replied, followed by a sigh on his end and some shuffling. The noise in the background, what sounded like the whir of a motor, got a little quieter.

 _"I get the impression you haven't been up here in a while, sir,_ " he continued. " _Off the record, I think you should know they haven't kept up their end of the promise to Sora. They've been testing every day. Steroids and testosterone recently. It's made the three princes far more aggressiv-"_

"I'm well aware…" Zeff replied, reaching up to press a hand to his temple.

" _And yet you've sat idly by and said nothing. Gotta say, I'm-"_

"I have a son to protect," growled the blond, slamming his fist against the control panel. "He met his first merman three days ago, and the risk is too high."

Smoker was silent for a moment, almost considering his words before he muttered, " _You trust him not to go to the Navy…?"_

But Zeff was quick to answer, annoyed the man had asked in the first place.

"Of course I do," he shot back. "If he found out where he came from though, that would be a different story. He's a stubborn, sensitive brat. But even still, I want no part and I mean it. You want help, go to O.H.A.R.A. But leave B.A.R.A.T.I.E. out of it. I want that on the record too if any of those brutes at HQ try and say I said otherwise."

Another silence on the other end, then a small huff of breath.

 _"Huh…"_ was all Smoker said, and it was simple enough to fill Zeff's tone with annoyance and a hint of disappointment when he replied.

"Objecting, kid?" he muttered. "Have your morals changed that much-?"

If that was the case, then this wasn't the same intern he'd worked with all those years ago. The kid had always been serious, and rather gruff. He was obedient to his superiors, but he'd known how to take charge of a research expedition, and it was clear he'd studied day and night.

Smoker knew everything there was to know about the world's oceans, and, even if he didn't show it outwardly, his heart was in the right place. His goal was to protect and preserve, and that was enough to stir in Zeff a great deal of respect for the younger man.

He was one of the few he trusted not to abuse the knowledge of the merpeople….

But despite all that, he wasn't ready. He wasn't ready to risk his stupid son's safety. He trusted Smoker, but not the people he now served. And to Zeff, family came first.

This was something Smoker seemed to pick up on when he spoke a minute later, his voice a little quieter, a bit more pensive.

" _It's interesting,"_ he mused. " _The way you came down on that kid back then... Never would've thought your world would shift this much either…"_

Zeff said nothing - nothing affirmative nor negative. There was no one that would understand what hopeful blue eyes did to him, a brave, vibrant smile that welcomed whatever the future held.

His life's focus had indeed shifted years ago, and it was not going back.

 _"You're on the record, sir. You have my word,"_ Smoker said eventually, his voice level.

"'Preciate it," Zeff grumbled back, and he was pleased, rather than put out when he heard the telltale click in his ear.

Smoker had hung up, pocketing his phone and finally climbing on-board the small boat bobbing gently next to the dock outside the lab, its motor humming gently as it idled.

Tashigi poked her head out of the small cabin at the sound of ropes plopping onto the deck as Smoker untied them.

"What are our coordinates, sir?" she asked, shooting a nervous glance back towards the building.

There were cameras watching, but considering the main crew had all joined the search party, they, thankfully, hadn't been questioned when the four of them came out to the docks.

"Change of plans, Tashigi," Smoker said simply as he straightened and crossed the deck towards her. "We're going to West Blue."

"What?!" she yelped instantly, Coby and Helmeppo glancing over from where they stood by the railing. "Why? What about-?"

"If that mermaid was smart enough to get them out in the first place, she'll keep them out of harm's way for now," Smoker muttered, cutting her off.

He pushed past her into the cabin, taking the wheel and slowly pushing forward on the throttle to start swinging the boat out of the small harbor himself.

Tashigi didn't look convinced though, standing rather nervously with an arm crossed over her chest, the other anxiously adjusting her glasses.

He wasn't sure it would help, to try and explain the situation, particularly since Tashigi had never met his old boss, Dr. Red. She'd only been out of school for a few years, and there was much she didn't yet know about the East Blue situation….

They were alone, for the moment, Coby and Helmeppo still outside watching behind them as Smoker circled the boat out away from the dock and picked up speed towards open water.

"Tashigi," Smoker said, drawing her attention back to him. "Have I ever told you about Dr. Red's son?"

* * *

"Yes, it's going to hurt, you baby, but it's _necessary!_ They'll know exactly where the colony is if they can track us any farther. Now give me your arm."

Maybe sticking out her own bleeding arm to gesture insistently for Yonji's was a bit intimidating, but for fuck's sake, he was a shark. Kuina had seen the three brothers squabble, bite, and bleed like it was nothing, and suddenly a knife poised over the tracking tag embedded just beneath the surface of his skin was that terrifying?

"Like hell I'm lettin' you do this!" the green-haired merman squawked, hissing and yanking his arm away when she tried to grab it forcefully.

"Fine," Kuina conceded, backing up in the water a bit and holding up hands. She offered the knife to his brother instead. "Niji?"

"With pleasure~" the other merman agreed with a low, sadistic chuckle, reaching out a hand for the knife.

"Like hell I'm lettin' you do it either!" Yonji screeched, swinging his tail around to whip a stinging lash at his brother's light blue tail.

A predictable growl from Niji, whose eyes darkened dangerously just before he darted at Yonji for payback.

But Kuina took the distraction to finally clamp a strong grip onto Yonji's arm, pulling him towards her in the water. Then it was a quick flick of her wrist, almost invisible, her skill apparent as the blade sliced a small, precise incision in the merman's forearm. Another small twist and the tiny, flat tracking chip slid out from beneath his skin to float up in the water between them.

Only then did the blood trail out, staining her white shirt the faintest bit of pink. She was a silvertip shark, but thankfully, she had enough control to keep any blood-triggered feeding instincts under control.

That couldn't be said for Niji, who was positively trembling, teeth bared as Yonji immediately squirmed with the pain, letting loose a string of curses.

Kuina rolled her eyes and turned to the other two brothers.

"Who's next?" she asked, giving the knife a teasing twirl in her hand.

Niji gave another unnecessary low hiss, hesitating, but it was Ichiji who reached out to take the blade calmly.

He ran his thumb over his own arm briefly, finding the old, barely visible scar from the chip's insertion years ago, and then he turned the blade on himself, repeating Kuina's process without so much as a flinch. He snatched up the tracking tag once he had it free and crunched down on it with his teeth to destroy it completely, shooting Yonji a withering look at his lack of tolerance.

Finally, it was Niji, and, not one to be upstaged, he grabbed the knife roughly from Ichiji's hand, then swiped the blade across his arm too, hacking out a chunk of skin, and the chip as well.

Niji scooped up his chip, as well as Kuina's and Yonji's, and chomped down on all three.

Kuina scowled at the amount of blood swirling into the water from his arm though, so she stripped down to her black sports bra, and ripped off a strip of fabric from her shirt with her teeth to tie tightly around his wound.

"This isn't going to stop them. But it'll make it a lot more difficult at least," she murmured as she did, ignoring Niji's grumbles of, "Too tight, dammit…." as the fabric pressed into his wound.

She held out her hand for the knife then, waited until Niji plopped it into her waiting palm. Then she slipped the plastic cover back onto the blade and stowed it into her backpack again, along with her ripped T-shirt.

A flick of her tail and she swam off again without another word, only checking over her shoulder to make sure the three mermen followed.

They'd hit a patch of vast open water, big enough to confuse any ships that pursued them, so it had been a place as good as any to get rid of those tracking tags.

Hers had been inserted first, soon after she'd been captured. They'd kept her inside, by herself, for a long while, but the day she cracked the glass of her tank after slamming countless rocks against it, her captors had decided to take precautions.

She hadn't known about her fellow prisoners for a good year…..and when her captors had finally let them meet, their compliance for their surroundings had shocked her. It was a wonder the brothers had agreed to come with her now, and she still didn't trust them to keep the secrets they were meant to.

But they deserved a chance, she told herself as she swam onward, believing in the innate sense that told her to follow the warmer currents, invisible, but undulating towards the east.

Years of her childhood she'd spent training to protect the royal family, or what remained of it. And it couldn't have been coincidence that she'd be taken directly to the three princes thought to be lost.

She didn't need to convince anyone, not even herself, that she was doing the right thing. She knew she was.

It was humans who'd wrought so much pain in her life, and with these three on her side, maybe, just maybe, the merfolk finally stood a chance for the justice they deserved…

* * *

" _Bringing a human! A_ _ **human!**_ _I can't believe this - you owe me_ _ **big time,**_ _Zoro! You're gonna find me a pet seal like you promised! A cute baby leopard seal so I can train it to bite your ugly face off when you annoy me!"_

Zoro ignored her.

For close to a half hour, he'd been listening to Perona bitch up ahead of them, essentially alone in his irritation considering Sanji couldn't understand her. Not to mention the blond was clearly in his own little world, staying close, but swimming off to investigate various mundane things with way too much eagerness, as far as Zoro was concerned.

At one point, he swam back over with a giant starfish in his hand, pointing at it excitedly and spouting human scientific jargon like Zoro was supposed to know what he was saying.

He'd gotten annoyed when Zoro had merely stared at him blankly, and swam off again.

Perona too had drifted away a few times, only to come rushing back to him telling _him_ not to wander off.

He knew where he was going, for fuck's sake!

Especially when, before long, more and more things looked familiar - the kelp forest, the squishy anemones growing on the rocks along the stone field just before the Great Trench.

And sure enough, before long, there were the two ancient columns, white marble encrusted with barnacles now, that stood on the precipice of the drop-off. They'd been there as long as anyone could remember, and it was speculated that they'd belonged to a human civilization at some point, one that had been swallowed up by the ocean.

It was all that remained, but it was a clear marker, as crumbling as they were. This was where they descended.

Sanji picked up on the significance of the columns as soon as he saw Zoro and Perona slow.

His eyes widened, and despite being underwater, a sense of vertigo came over him when, after passing between the columns, he found himself staring down into a deep, wide trench that rivaled any canyon he'd seen above water.

It was deep, and far darker than the sunlit water above them, that glistened over the field of scattered white rocks leading up to the columns, like the rubble of some mystical ruins.

He hesitated, feeling his heart flutter a bit, especially when he spotted a strange structure far below, emitting _light_ from inside, it looked like.

"What is that….?" he murmured, trying to make it out from this distance.

Perona just rolled her eyes and muttered, "Come on," diving over the edge of the trench to start swimming down towards it.

Instead, Sanji turned to Zoro, his heart now thumping hard.

"Zoro, what _is_ that?" asked the blond.

The merman just shrugged and grinned.

"Where us live," he answered, then stretched out a hand towards Sanji, who stared at it for a second before taking it.

As soon as he did, Zoro's fingers closed around his and he gave a hard tug, dragging him over the edge as well.

There was no choice but to follow, and Sanji was rather amazed that, even as they swam much deeper, his ears didn't pop.

Instead, he swam comfortably behind Zoro, glad they were underwater, because he was pretty sure his hand in Zoro's would be sweating right about now.

The structure grew larger the closer they got, and surprisingly, as the light grew dimmer, Perona's lower half began to glow, bioluminescent pinks and purples giving them something to focus on as they descended.

It was quiet, and Sanji's anticipation mounted, even as Zoro looked back and stole confident smirks at him every now and again.

Sanji tried to focus on him instead, on his face, the glimmer in his eyes. Sanji found himself wondering if his own eyes had changed with his transformation as well.

Eventually, Perona's voice rang out, the mermaid turning around to look at them, tentacles still pumping her along.

" _I got you here, but you're on your own now, Zoro!"_ she called out. Then, for Sanji's benefit, she switched to his language. "I said you're on your own! Good luck not dying!"

" _Fuck you!"_ Zoro called after her, and Sanji judged it was some kind of insult when he flashed a very human middle finger.

He was hardly paying attention to that though, because his focus had shifted entirely, in awe of what lay before him.

It was a sunken ship, of all things, and a giant one at that, an old-looking cruise liner with four huge smokestacks and everything. It had to be eleven stories tall, and it looked to be in astounding shape, somehow, despite being located at the bottom of a fucking ocean trench. Its exterior was polished enough that he could even read its name on the starboard side.

"Wait - the _Noah?!_ What the fuck?! _The_ Noah?! The cruise ship that sank fucking - ninety years ago and was never found - are you _kidding me?!"_ Sanji screeched in disbelief, wrenching his hand from Zoro's grasp so he could run it back through his hair, then grab the merman's shoulders and give a hard shake for no reason.

Zoro snickered, feeling Sanji's arm come over his chest until the blond was practically hanging off his back like a sea monkey.

The merman nodded casually and said, "Let's go in," though it earned him a hard smack from Sanji a second later.

"Would you fucking wait just a damn second?! I wanna take this in, dammit! _Fuck_ , I should've brought a camera!"

Zoro made an impatient noise, but stayed put while Sanji admired, not really understanding his fascination. They had boats like this in the human world, buildings that were even bigger. He'd seen pictures. So why was something like this so damn interesting?

But to Sanji, of course it fucking was!

There were _merpeople living here!_ He could see lights and movement inside the ship, through the rows of circular windows, some of which were open, most likely as an easy exit into open water.

He knew for a _fact_ ships this size could hold thousands of passengers, and thus, he had to wonder just how many merfolk called this place home. It was almost too exciting to accept as truth. How the fuck could something like this stay out of humans' radar for so long?

He wasn't sure how many minutes he'd been gaping at the sight before Zoro jerked his head back to lightly knock him in the nose, much to Sanji's irritation.

"Let's _go,"_ he whined, and started swimming, dragging Sanji, still clamped onto him, along.

Perona had disappeared at some point, Sanji realized, and suddenly, it was just the two of them and they were _going inside_.

He let Zoro tow him, just until they reached the deck of the ship, which still had benches bolted down to the wood, old shuffleboard courts, and even some ropes floating up like coiled snakes ready to strike.

It felt like a trip back in time, Sanji craning his neck to look up at the giant orange smokestacks that rose up far above them.

Only when they reached the pair of grand-looking doors that served as the main entrance to the ship's interior did he let go of Zoro's shoulders and hover beside him.

The metal doors were large, adorned with elaborate porthole windows shaped like blazing suns.

Zoro pushed them open with ease, and Sanji hesitantly followed him through into a fancy entrance hall, a short staircase leading down to the floor, which sprawled out to a balcony overlooking a spiraling staircase that twirled up yet two more stories and down to a lower level on one side of the room, other open doors leading to hallways on the other.

Around the room were several sitting areas, complete with historic sofas and chairs, some of which had clearly seen better days, barnacles and sea plants growing on them….and some of which were occupied by merpeople, lounging and conversing in the foreign language Zoro and Perona had used.

At first glance, Sanji could recognize a sailfish mermaid, a rather husky grouper merman, and a long oarfish merman whose tail curled all the way around a sofa to keep it out of the way.

"Holy shit…." Sanji murmured quietly, and despite all there was to comment on, the first thing he said when Zoro turned back to grin at him was, "How the fuck do you guys have electricity down here?"

Zoro furrowed his brow in confusion, so Sanji pointed insistently up at the lit chandeliers overhead, the filigreed lamps mounted on the walls.

"Lights?" he tried again, and Zoro finally seemed to get it.

Not that he knew how to explain it.

"Franky….gave…...they charge - we charge up - charge station - above water-" he stuttered, eventually having to fix Sanji with a rather helpless look.

"A generator?" Sanji asked, but this only made Zoro roll his eyes. Like he fucking knew what that was.

"Ask Franky, Question," he said instead, and nudged Sanji towards the dramatic staircase, shouldering him gently to break the way the idiot was gawking at the merpeople relaxing in the room. "Don't _watch_ …" he gritted out.

"You mean 'stare', stupid," Sanji muttered as he swam after Zoro, still trying to steal glances when he could, albeit less obviously. "And no one's even paying attention! I'll stare all I damn want, considering-"

"Shut up," Zoro interrupted smugly, putting his newly-learned phrase to good use.

"Ugh!" Sanji groaned, flicking his tail to quickly follow after him until the two were at the top of that staircase. "Where are we even going?"

"To see Queen!" Zoro replied as he descended, irritated that he had to repeat it for the thousandth time. Thus, he missed when Sanji froze in response.

Zoro had already rounded the first landing of the stairs by the time the shock dissipated from Sanji's system, the blond darting after him quickly.

"Mosshead!" he called, but Zoro ignored him, just kept going down, the marble stairs opening onto another smaller, but no less elaborate, hall, also warmly-lit, its wood-paneled walls adorned with rich tapestries that billowed gently with the water's movement.

The tapestries depicted detailed scenes of heroic battles just as any would in museums or the like….save for the fact that these illustrated scenes were of stylized _merpeople_. That was new.

Not to mention, there was a sheen to them, and Sanji quickly realized they were woven out of bits of plastic bag! Trash left by humans...?

There were more pressing matters at hand though, namely the fact that Zoro kept on swimming, despite Sanji's mounting panic.

"Hey! Mosshead!" he tried again. Then, " _Zoro!_ Wait!"

This finally got the merman to stop, the algae-head throwing up his arms in frustration.

"What?!" he growled, rounding on Sanji, just barely stopping himself from fucking whacking the blond.

Sanji had lifted a hand to pinch at the bridge of his nose, brows scrunched down with worry.

"I don't-" he said. "Hold on. Just - give me a moment. This is way too much to process and-"

"You're prince!" Zoro shot back. "What's - problem?"

"No, I'm not!" Sanji insisted.

But then, a look came over Zoro's face. A look that was angry and entirely hurt, and it was something he didn't want to see there.

If he could have, Sanji would have let loose a heavy sigh.

He was just glad they were alone for the moment, the hallways that branched off on either side of them devoid of life too, save for a few patches of vivid sea coral that clung to the walls and ceiling in places.

Sanji squeezed his eyes shut for a moment, then found himself swimming over to take hold of Zoro's shoulders, his tone softening.

"Look," he murmured, still under the wary scrutiny of Zoro's wounded gaze. "Okay. I'm starting to think maybe you're not just fucking with me about this whole thing. But that doesn't change the fact that I _haven't been here._ Perona even said it. Even if I was - _born_ royalty or whatever, _somehow,_ how can anyone here see me as their prince if I've done nothing for your kingdom? I want to, but - I couldn't even do anything for you - or - or anyone! And now you're going to cart me in to meet my long-lost-"

"But you want to," Zoro cut in, relaxing a little, latching onto one of the few things he'd understood from that spiel. "Want to help."

" _Yes_ , but-" Sanji replied instantly, though he trailed off, hands leaving Zoro's shoulders to cross over his own chest uncomfortably, eyes averting. "Zoro, this is a lot."

There was something about the nervous blond before him that made Zoro's initial anger dissipate, replaced with a want to protect.

But it was a strange sort of protect. It came with the odd desire to slide fingers through his hair and hold him until that fierce determination returned to his eyes.

It was a different feeling from his innate instinct to protect the Queen. It was a softer feeling, something that felt far more in the realm of the toned-down emotions he'd felt as a human. The same side of his brain that told him Sanji's touches felt damn good and that he looked pretty damn attractive, even in dumb human clothes.

And it was a feeling very much tied to the flash of passion he'd felt earlier before Perona had interrupted.

Whatever the feeling was, it made him feel a hell of a lot better about his fumbles above the water. Sanji clearly didn't have a fucking clue what he was doing down here either.

"Scared?" he eventually asked with a challenging grin, and when the blond simply looked infuriated at the merman's parroting of his own quips, Zoro figured he'd won.

Just then, however, any plan for how he'd intended to introduce Sanji was effectively thwarted by the sound of a door opening down the long hallway to the right of the staircase.

Zoro and Sanji both turned to see a figure swimming out, a young mermaid by the looks of it, wearing a tight, low-cut pink shirt with a yellow swirling pattern.

Her tail was a surprising saturated pink, though it was clearly that of a thresher shark, long caudal fin trailing out behind her like a string.

It matched her hair, also pink, pulled back on one side by a headband, though the other side covered half her face.

"I must say, Zoro, I'm impressed," the mermaid said as she swam closer, a smirk tilting up her lips. "I don't think I've _ever_ heard you use human language outside of lessons before~ Who motivated _you_ to practice?"

Her gaze shifted to Sanji's face, though the merman's jaw had already dropped, especially when he saw that swirling eyebrow, so similar to his own, a mischievous glint in her visible blue eye.

Neither him nor Zoro said a word. Not even Zoro, who'd seemed so confident up until that moment.

The dumb mosshead merely stuttered out, "Uhh-" unhelpfully.

It didn't matter though, because the mermaid had noticed. She recognized her own features staring back at her.

But, more strongly, she recognized her _mother's_ features.

That blond hair, the softly pointed nose….her mother's kind eyes. It had been so long. She barely remembered her mother aside from the photos she'd seen, but this merman was….

" _Zoro, who is this,"_ she demanded quietly in her own language, eyes not leaving the familiar stranger's face.

Zoro gave a slightly sheepish wince at her tone, the threat of a bad reaction finally hitting him.

" _Um…Queen Reiju…"_ he mumbled, flicking his gaze between her and the baffled blond. _"I, uh...thought you'd wanna meet your brother..."_

* * *

Something was off when Zeff drove the small boat up to the docks outside B.A.R.A.T.I.E. It was a little past midday, and things were quiet.

That wasn't the strange part.

There was just something in the air.

He knew he was right as soon as he saw a suspicious pair of khaki shorts, a polo shirt, flip-flops….and a telltale lanyard all piled together on the dock by the water.

He saw it before anyone else as he brought the boat to a final halt in its proper spot, but Patty's voice from outside announced it not long after.

"Hey, boss!" he called, leaning on the rail by the offending evidence. "What's Sanji's shit doin' here?"

Zeff didn't reply, already feeling a creeping dread take hold of his chest.

He kept his face passive though as he shut off the boat and swiftly turned out of the cabin.

"Probably out for a dive," he grumbled. "That brat never does ask for permission."

His slightly uneven gait clomped across the deck, bypassing the two men and disembarking without further word.

"Take care of things here. Bring the samples inside. Got a phone call to make," he muttered as he stooped to pick up Sanji's belongings and shove them under an arm.

"Another one…?" Carne mumbled in the background, but Zeff was already halfway down the dock to the building, with the rather urgent intent of getting back to his bungalow.

His phone was out of his pocket and his thumb was punching out a number as soon as he was out of earshot.

The dialed number rang and rang, until finally, a smooth female voice picked up on the other end.

Zeff's tone was curt, skipping formalities entirely when he replied.

"Dr. Nico. You wouldn't happen to have any idea where my son is, would you?"

* * *

"Sir, we've lost signal on them!"

"They're completely gone! Like they just vanished!"

Cigar smoke engulfed the man's head, eyes, shielded by the brim of his white M.A.R.I.N.E.S. cap, closing in silent irritation at the panicked cries of his crew members.

He didn't move from his spot at the bow of the ship, the largest one the M.A.R.I.N.E.S. had, essentially a floating laboratory built for lengthy voyages and capable of transporting animals of great size, most notably a bull orca a few weeks ago.

"Dr. Sakazuki! Sir!"

He already knew exactly what had to have happened. That damn mermaid must have destroyed their tracking tags somehow. There was no way they'd gotten killed or maimed.

This was a problem. The mermaid had always been surly and defiant, far less cooperative than the three mermen. But he supposed that was what happened when a fish was captured too late. There was no hope of taming them fully. Not like the mermen, who'd been hand-reared at the laboratory since they were babies.

Of course, they'd had their mother with them for a time, but she hadn't survived long, after injecting herself with that solution before their birth. And honestly, it was for the best. She would have surely filled their heads with thoughts of freedom far sooner.

"Dr. Sakazuki, what should we do?"

His crew was still pestering him, so he finally turned on his heel, cigar still clamped between his teeth, pulling up the collar of his Hawaiian shirt.

"We keep moving east," he said simply, dress shoes striding steadily past the others, even as the boat tilted and rocked with the waves.

"But - sir-!"

"There are other ways to draw them out…." he insisted, slipping through the doors to the main cabin.

He owed a call to a certain Zeff Red….


	8. Hooked on a Feeling

_This place was nothing like O.H.A.R.A. It was cold, and clinical, and while the tank might have been wide and deep, with all the proper vegetation to simulate the real ocean, it didn't come close. There was no gentle rise and fall of life, and the fish that did flit about were listless, their eyes dull with boredom and lack of stimulation._

 _She'd willingly agreed to this though. She'd chosen this. Her children's lives came first._

 _Reiju was safe; Sanji was safe. And while her three small sons, barely a month old, bundled up in blankets of sea kelp on the flat rock before her, were now trapped as well, she was with them. And as long as there was that, she would protect them. There was nothing that would harm them while she was here._

 _Still, her hand trembled as she reached out to stroke her babies' soft hair, first Ichiji's tuft of sparking red, then Niji's electric blue, and Yonji's kelp-like_ _green. The boys slept soundly, tilting unconsciously into her soft touches, completely unaware of the circumstances that had brought them here._

 _She sighed, watching their little tails swish back and forth gently in the water. They were beautiful, perfect, hands curled in tiny fists, bubbles escaping their mouths every now and again from between short nubs of sharp, jagged teeth, already growing in._

 _They'd been bigger than Sanji, these three. Sharks grew faster, matured faster, than humans._

 _Sanji had been so small, smaller than even Reiju had been, and the birth far more difficult than her daughter._

 _Multiples were one thing, but she'd had to do it on land, not knowing if the serum had worked. She'd hoped desperately, but hadn't known for sure. And she did not want to risk her babies drowning, should they come out human._

 _Only one had…..and despite it being beyond her control, she couldn't help but feel like she'd failed the other three somehow. They were in danger, and even Sanji had been….even Sanji._

 _That was why she was here. To protect him. To protect all of them._

 _If the M.A.R.I.N.E.S. kept their word…_

 _Outside the tank somewhere, a door slammed, a muffled sound, but she still startled, automatically curling over her sons protectively._

 _Her long blond hair floated around her, covering one of her blue eyes as she craned her neck, looking up towards the surface between schools of slow-moving fish, up at the distant orbs of fluorescent lighting that mimicked more than one unnaturally white sun._

 _When she saw his form come into view on the platform high above, shadowed and undulating with the water's slight movement, she gave a low hiss automatically, something she hadn't done in a long time. She was gentle, a pale blue nurse shark with no intention of hurting anyone._

 _But this man….she'd do what she must._

"Mermaid," _he called down in the human language, which she understood, but had no desire to speak unless with_ _ **friends,**_ _those she knew or trusted….the scientists at O.H.A.R.A., who had taught her, or Dr. Red._

"Mermaid," _the shadow man said again, voice audibly gruff and serious, even beneath gallons and gallons of water._ "I request your company. I won't call you again."

 _Her heart in her throat, she shut her eyes for a moment, then shifted her babies into a bed of soft sea plants that floated and wove gently around them, capturing them safely in a cushiony nest._

" _I won't be long, my loves," she murmured to them in her own language, bringing a smile to her lips, even though their eyes were closed. She wanted them to hear it in her voice._

 _Fingers brushed over each of their chests before she reluctantly gave a swish of her tail and swam up from the bottom of the habitat, straight up alongside a towering bed of rock, a sorry imitation of an undersea cliff, until she reached the surface._

 _Bravely, she poked her head and shoulders right up, a furious, but silent frown tugging at her lips, harshening soft features._

"How intimidating," _Sakazuki said sarcastically, eyeing her from where he stood on the flat metal platform that jutted over the water. It was meant for feeding, but he used it as his throne, eyeing her with stoic disdain, not bothering to get down on her level._

 _The room was vast, nothing but endless white and cold sounds, dripping that echoed in the white space. Pipes criss-crossed the ceiling, and it was nothing like the luminescent turquoise of O.H.A.R.A., the beautiful grotto that was homey and welcoming, where she could come and go as she pleased._

 _None of the scientists working at lab benches around the outskirts of the room even spared her so much as a kind glance._

 _This wasn't the only tank in the room, and she feared what was inside the others…_

"If you're expecting me to address you as Queen Sora, as those emotional fools at O.H.A.R.A. do, then I'm afraid you will be sorely disappointed. You have volunteered to be our specimen, and a specimen you shall be," _Sakazuki stated, crossing arms over his broad chest, the floral-patterned shirt that stood out among the matching white jackets of the other workers, all with the M.A.R.I.N.E.S. blue logo printed on their backs._

"I expect nothing more than for you to stay true to your word," _she said boldly, her voice miraculously level and strong, despite the nervous pounding of her heart and the horrible feeling of revulsion that rose in her throat just looking at this man._

"You may do as you wish to me, but you will not harm my children," _the Queen insisted._ "If my sons are to be kept prisoner here, then they will receive the best treatment and care you have to offer. Use me as your object of study, not them."

"We intend to," _Sakazuki replied quietly, and then, to the Queen's surprise, his heavy boot stepped closer to the edge of the water as he reached his hand out._ "And that starts right now."

 _It was a human gesture, she knew, as she eyed the tanned hand warily. It was used for greetings, or to show agreement._

 _Unfortunately, she had no choice but to trust it._

 _Her jaw clenched. She gathered her nerves and swam over, as proudly as she could manage given the circumstances._

 _She reached out to place her hand in the man's._

 _He gave a hard yank, pulling her up onto the platform roughly, her shoulder slamming into the solid surface. She yelped in pain, but Sakazuki only gave her arm another tug, this time throwing her towards the steps leading down to the floor below._

 _Up them came two more uniformed men, one gripping her under the arms, his fingers tense, tangling in the netting she wore wrapped around her chest as a top. He pulled her up off the ground while the other man grabbed her tail._

 _She thrashed, but she was weak. She was still weak from the serum, from bringing her sons into the world mere weeks ago, and now from oxygen loss. Her gills twitched fruitlessly, her body burning all over, screaming for water, but she thrashed with all her might, raspy growls and noises that tried to sound like a voice raking from her throat._

 _The men wouldn't release her._

 _And the second she saw two others flop onto the platform, those silly human flippers on their feet, slapping towards the water, her_ _ **sons**_ _, she lost it._

" _No! No - you promised!" she managed to scream, though the panic clouded her mind, human language slowly slipping away from her in that moment. "Don't take them - don't hurt them - no!"_

 _The flippered men stripped off their shirts and dove into the water, disappearing below the surface as the two holding her started to drag her down the stairs._

" _You - You can't - no - my - my children-!"_

 _A choked sound. She couldn't breathe, and her body was starting to slump heavier and heavier in the men's arms. Black dots began to cloud her vision. The sound of her blood rushing sluggishly was deafening in her ears._

 _Her sons…. Her precious sons. She'd done everything she could to protect them. She_ _ **had**_ _to protect them…._

 _Sakazuki's voice in her ear._

"Don't worry. Sharks are born to be without their mothers."

 _There was wetness on her cheeks, streaming from her eyes, and the last she heard was that same evil voice muttering something about a lab, something about paying a visit to B.A.R.A.T.I.E. to collect the last piece-_

 _No. Sanji._

 _She couldn't breathe…_

 _Her sons…_

 _Her vision faded to black._

* * *

It was so blue. Even with an orange light blazing behind glass on the wall, it only served to cast blue shadows over the room where Sanji now sat, or rather, floated. A lounge room, with couches and chairs, fabrics of reds and pinks draped around them from the ceiling, rippling in the water.

There was an old wooden desk against the wall, a few twirls of purple sea plants curling up the legs. On the desk sat a stack of books, all of which were covered, the pages too, in sheets of clear plastic to protect them from the water.

The tables were covered with odd things, insignificant trappings, small jewelry boxes, bottles, pebbles, even a few dolls that Sanji distinctly recognized as toys from a fast food chain. All of it was arranged artfully, as if the objects were treasures. Perhaps to a non-human, they were.

The Queen, his _sister,_ sat with her tail curled on an old-fashioned settee across from him, one that had seen better days, the maroon velvet of the cushions torn in a few places.

Uncomfortable under her icy blue gaze, Sanji thought of Zoro, whom she'd forced to remain outside. If she was going to have this talk, she wanted to have it in privacy.

The blond had to imagine the mosshead was stationed as close to the door as he could get though…

He almost wished Zoro had shoved his way in anyway, considering how damn awkward he felt.

"You shouldn't have come."

Those were the first words out of his sister's mouth, her voice stern and serious, pale skin almost translucent in the cold light. She truly looked the part of a siren of legend, and Sanji had to try hard to focus, try not to lose himself in the unbelievable fact that he sat here, in an underwater mansion, essentially, across from a _real_ mermaid.

He could very well be dreaming, could still be at home in his bed, with Zoro beside him….and okay, why Zoro was included in that fantasy was a damn mystery….

He finally managed a short humorless laugh, that was more of a scoff than anything.

"Not even gonna offer me a drink first," he muttered, before he realized how stupid that sounded, given where he was.

"This isn't a joke!" Reiju replied irritably.

"Yeah, well, I figured that much out!" Sanji shot back, unsure why he was being so hostile, to a lady nonetheless, even if she was his supposed sister. "If someone could explain to me _why_ I shouldn't have come, that would be great right about now, 'cause I haven't heard a good reason yet!"

Reiju's pink lips tilted down in displeasure, her long tail fins twitching with agitation. She settled back against the cushy throw pillows, which sat heavily against the armrest of her couch.

"How much do you know?" she asked cautiously.

Sanji's shoulders slumped in an imitation of a sigh before he shrugged slowly and held hands up in some show of surrender. He wasn't here to push buttons.

"I just - Zoro showed up with the bracelet. I guess he got it at O.H.A.R.A. I don't know," Sanji explained. "I wanted to try it. And I did. Then he told me I was one of you…. That was a few hours ago. And that's about all I've managed to gather. I don't even know how this thing works really..."

The blond twisted his wrist around to examine the thing absently. His fingers brushed over the cool metal, and though he could feel the two small prongs digging into his skin, it was only a small sensation, like a splinter, not unbearable if he didn't press on it.

"Our father was a scientist, and he made five of them," Reiju murmured, her voice quieter now, more tired than angry. "He'd been researching mimic octopi and managed to create a serum that could induce such changes in merpeople."

Sanji's head spun. Earlier, Zoro had tried to get something out about his father - his birth father? - but his terrible language skills had rendered his point near unintelligible.

"A - A serum?" the blond stammered. "What is this, some superhero movie shit?"

Reiju shot him a look, a look that was unamused, urging him to be patient. Actually, it was a look quite like that of an annoyed older sister.

"He believed in power, but also protection," she continued, once Sanji had quieted, focused himself on listening again. "He was the King of our colony, and he thought the ability to transform would allow us to acquire more territory, let us move ourselves to escape the Navy's weapon testing. It wasn't safe.

So, after much failure, he managed to create the bracelets, which he infused with the serum. Only a small amount is necessary to maintain the transformation, provided it circulates continuously through the blood. Removing it stops the injection of the dosage and thereby ceases the transformation."

The look on Sanji's face must have quite obviously spelled his confusion, as Reiju quirked a brow and asked, "Got all that?"

Did he? It was all so unbelievable, and without the scientific specifics to back it up, he still wasn't sure how it was possible. Unlocking this key to transformation would be revolutionary, in the medical field especially. How could such a serum exist and the rest of the world be completely unaware? It was true a mimic octopus could be capable of transforming its shape, color, and texture at will, but changing DNA? It was beyond the reach of Sanji's imagination...

His eyes drifted, again, to the bracelet on his wrist, then to his own tail, through which blood circulated, water moved through his gills. He could move it, feel it. It was _real._ Perhaps, given how his life had been turned upside down in the last few days, it was best to suspend his disbelief about such things.

"I still don't-" he started to say, but shook his head, forcibly shutting off the scientific part of his mind that wanted answers in favor of groaning. "Ugh. Alright, fine, so it's a thing. There's not...a time limit, is there?"

The terrifying thought of turning back, _here_ , hundreds of meters below the surface, inside a sunken _ship_. Even if he had help getting to the surface, the pressure alone would likely kill him.

"Not in the final ones he made," Reiju assured, a tiny smirk coming to her face at the tension swiftly leaving his. "Though, as I said, there were only five."

"This still doesn't explain how I'm a merman…" he muttered, clarifying after a second. "I mean how - I've been human up until now, but…."

Reiju had a quick answer though, again fixing him with a scolding look, as if to doubt he'd really been paying attention.

"Yes, it does," she said. "Father made one for each of us. So that we might be able to escape first."

Again, Sanji's brain did a flip, struggling to stay on track with her explanation.

"Each of us…?" he mumbled, resisting the urge to scratch at his hair lest he look even dumber.

"You, myself, and our three brothers," she said, counting on her fingers until she held up five.

"Hold on - _brothers?!_ " Okay, now he was officially stunned, something his sister elected to ignore. If he was going to learn the facts, then she was going to explain them without interruption.

"Father decided to attempt a negotiation with the M.A.R.I.N.E.S., to seek an alliance to stop the weapon testing. He offered the bracelets as proof of his scientific prowess, but the M.A.R.I.N.E.S., predictably, were greedy and jumped at the chance to experiment.

They pursued the colony, tried to steal the bracelets. He managed to entrust one to O.H.A.R.A., though two were destroyed and two were lost, stolen by the M.A.R.I.N.E.S. or-" She shook her head. "It's impossible to tell. Father tried to attack a M.A.R.I.N.E.S. ship, but was pulled aboard. Witnesses from O.H.A.R.A., who attempted to aid the merpeople, report that he was killed."

Sanji was speechless, his jaw having fallen open somewhere along the line. The way Reiju made her statements was so clinical, so detached. She sounded exhausted. Too tired of caring, too tired of dwelling.

It wasn't rehearsed though, that much was clear. Of course it wasn't. She'd likely never expected to explain this to anyone, let alone her brother, whom she'd never intended to meet.

He was here though, and it was surreal, because Reiju still saw her mother sitting there, blond hair floating around his face, blue eyes wide with concern and an overwhelming empathy that she could sense coming off Sanji in waves.

It was a strange feeling, a heavy one, and she looked away from Sanji, fixating instead on the tassels of the oriental rug positioned beneath the furniture, floating up and waving softly with the water's movement.

"Our mother was pregnant with you and our brothers at the time," she murmured, thinking back to what Dr. Nico had told her. "And despite taking our father, the M.A.R.I.N.E.S. were still in hot pursuit of our colony. There weren't going to be enough bracelets for each of us, however. So I'm told she injected the last of our father's serum into herself, in hopes that it would change the four of you…."

Realization hit Sanji immediately, and he must have made a soft noise of disbelief because Reiju flicked her eyes back to him, eyes dull and serious.

"Her blood rejected the serum, and it nearly killed her," she said. "And only one of you came out human…"

Sanji averted his eyes, which now burned, along with his throat. His entire life. His entire fucking life, he'd thought he was abandoned. Resigned himself to, if not resented, the fact that his parents dumped him...

"Did she….send me to live with-" he muttered, now staring hard at the same tassels his sister had studied only moments before.

"With Dr. Red, yes."

He shook his head slightly, swallowing hard, glad for the water surrounding him because it meant any tears that fell would be less visible. This was ridiculous. All along. _All along._

"What...happened to her…?" he asked quietly, knowing he had to, but almost not wanting to now. He could infer, after all, and it wasn't pretty.

It wasn't.

"The M.A.R.I.N.E.S. captured her," Reiju replied. "Or rather, they wanted you and our brothers, in particular. She offered herself up to them willingly if they would let you go free with Dr. Red. They took her and our brothers."

He'd known, after what he'd learned at O.H.A.R.A. He hadn't known then, but hearing this now, he'd known before she said it, and his chest clenched, a feeling he'd never felt before twisting in his gut. It was somewhere between remorse and rage, mixed with regret and grief, which he _knew_ he had no business feeling when he'd grown up so content and oblivious.

There was nothing he could say to remedy any of it. An apology would be too distant, but commiserating would be too selfish.

All he could mumble was a pathetic-sounding, "They could still be alive-"

Reiju cut him off before he could say anything else.

"They're dead. Dr. Red told us," she stated coldly.

It stung. Her tone was bitter, and he could only wonder how she'd made it on her own, with the burden of _knowing_.

Did he even have the right to ask?

"A-And you?" he stuttered out, barely audible. "How did you-?"

Again, she cut him off.

"Mother told me to swim away when the M.A.R.I.N.E.S. came. I barely remember it, but I hid. When I came back, Mother was gone. Everyone was gone."

A long silence followed, neither having anything to say. Sanji got the feeling she was done talking about this. He supposed he should be grateful she'd even told him what she had.

 _Fuck_ , it was a lot. On top of everything? On top of his fucking _tail?_ He'd given Zoro a hard time too...acted like he was the crazy one...even if he was still an idiot…

Still, he came back to one question, and it was one that almost hurt him more than all this newfound information.

How could his dad not tell him….?

Instead, he asked a different one, forlorn.

"So the M.A.R.I.N.E.S. know about me…." he muttered, remembering what Reiju had said, a feeling of guilt tugging at his chest. "Why haven't they come after me?"

She shook her head, averted eyes and stared at a wall, her hands holding her upper arms almost protectively now.

"That I don't know…" she replied with a long shrug.

Her voice was quiet, but it seemed her answer was true. There was an air of confusion, of hopelessness, in her tone. She wasn't hiding anything. She simply didn't have the answer.

And again, she wouldn't look at him, and he wondered why that was. He probably didn't have a right to know. He certainly didn't _feel_ like he did.

Fuck. Part of him had always wondered what it would be like to have siblings, wondered why his dad hadn't adopted another. It hadn't been a problem, but when three of his closest friends were a trio of brothers who were closer than anything, there had always been that thought in his mind. That somewhat jealous desire to have someone like that.

Yet, here his sister sat, a _mermaid_ , but his sister first and foremost.

And there was probably nothing salvageable.

"I don't blame you if you resent me," he murmured quietly, watching her, trying to picture what his mother had looked like, if Reiju's appearance was any clue. Had Reiju ever looked at him when he was a baby? Had she ever held any love for him?

Slowly, Reiju shook her head, lips turning up faintly, as if she was remembering something, and he realized she was looking at a glass case on a chest across the room. Inside the case was a photograph. He couldn't make out the subjects, but it set his heart pounding faster nonetheless.

"It's not your fault," Reiju replied, still with that smile. "I say you shouldn't have come, because there's no telling what will happen if it's discovered you have the bracelet. But...I suppose part of me is incredibly intrigued to meet my little brother…."

Her eyes flicked to his again, a little more relaxed, as if one layer of a mask had peeled back to reveal a glimpse of something softer underneath.

Despite the pain in his heart, Sanji's lips tilted up a little as well.

* * *

 _ **East Blue**_

* * *

Kuina's instincts, first, had told her they were getting close, but as soon as she saw the ocean floor slowly start to slope upwards, as soon as she saw the beginnings of the vast stone field, she knew.

These were the same rocks she and Zoro used as a play battlefield when they were young. They'd found two pointy human weapons, long forgotten in an empty room inside _Noah_ , and they'd waged an all-out war on each other, slashing the weapons about like dueling swordfish all day.

The rocks had dwarfed them then….but now they seemed far smaller than she remembered...

"If they're good for anything, they'll welcome us back with open arms!"

Yonji's voice drifted up to her from where the three brothers swam a few tail-lengths behind. It wasn't one she particularly wanted cutting through her tender memories.

He'd reminded her of Zoro when they'd first met, all brute strength, that green hair and tail.

But any comfort she might have leeched from that was shattered as soon as he'd opened his mouth...

"Listen. Ground rules, okay? You can't go barging in there announcing yourselves as the lost princes! We don't know how they'll respond, especially knowing the M.A.R.I.N.E.S. could be after us-" Kuina insisted, flipping herself around to face the three brothers.

Niji and Yonji shared an eye roll, or at least Yonji shot one his way, Niji's eyes hidden behind his sunglasses. It was enough to grate on her already-heightening nerves.

"This is serious!" she grumbled. "If you pull any shit…"

She looked to the redhead, the most sensible of the three, certainly the most mature, when he wanted to be.

"Ichiji, are you not gonna back me up on this?" she asked, hoping she could scrounge up at least some support. She hadn't left the lab in fifteen years. The brothers had _never_ left, and now they were essentially entering into a completely foreign culture.

There was no telling how much had changed in the time she'd been gone. _She'd_ changed. And as much as she wanted to return, she didn't want to be haunted by memories she _couldn't_ change…

She needed support.

"For once I will," Ichiji replied, and Kuina couldn't help it. Her eyebrows rose a little in surprise.

"We keep our mouths shut for now," he continued, voice calm as he crossed arms over his pale chest. "Listen and observe. Yonji, you especially."

Yonji copied him with a cheap imitation of his voice and a stupid facial expression, which made Niji snicker meanly.

Kuina waited until the two had swam down lower to examine some of the rocks scattered below them on the sandy floor. Then she slowed to meet Ichiji.

"Thank you…." she muttered quietly, and he simply shrugged without replying.

Her lips turned up a little, wondering briefly why he hadn't taken the opportunity to throw her gratitude back in her face with something cheeky.

But in fact, he remained quiet, and he had for a while now, almost like he could sense their impending arrival too, despite his own years away.

Kuina decided to try her luck, asking, "Are you nervous?"

It brought a proper scowl onto Ichiji's face, quickly enough that she chuckled.

He brought the tip of his tail up to whip at her face, though she caught him with the meat of hers, smacking him on the side, creating a flurry of bubbles and a red welt on his fair skin.

He didn't fight back though, beyond some more scowling and grumbling, and she had to assume the answer to her question was a definitive, 'Yes.' It wasn't often that Ichiji passed up an opportunity to assert his dominance.

Instead, he lengthened the distance between them with a frown and changed the subject.

"So our sister's the queen," he muttered, eyes firmly fixed on the blue ocean before him, the faint shimmer of scales from a school of tuna that swam ahead of them.

"She was, fifteen years ago," Kuina replied with a shrug, humoring him. "Unless anything's changed..."

She wasn't aware of the M.A.R.I.N.E.S. capturing anyone else. And that Tashigi girl, the one she'd impersonated, had said they were the only ones at headquarters. But there was no telling about elsewhere….at B.A.R.A.T.I.E., for instance.

"What about the other one?...The human?" Ichiji asked, as if reading her thoughts. "The one our mother let go?"

Her stomach turned at the thought, even if she knew it was illogical. Just the thought that one of their brothers had escaped was both hopeful and devastating at the same time. That one was living as a human. A merman by blood, but not body….and thus, a threat.

"Still living in East Blue as far as I know…" she said, trying to keep her mind from that last image of Zoro, caught in a net, thrashing and flailing to be free but losing the fight. Calling her name.

"Che...must be a cushy life," Ichiji muttered bitterly. "A human. Blissfully unaware of any of the shit happening right under his nose."

He had a point. Sanji had been damn lucky. Lucky to be born different. Had he not, he would have been right there beside them, most likely. But that was just it...

"Look, humans are the source of all my problems," she murmured. "But even I know that's not fair. It wasn't his choice…"

Ichiji wasn't done though, and Kuina had to wonder how long he'd kept these thoughts to himself, because she sure as hell hadn't heard them.

"It was his choice not to come help us!" the redhead insisted. "Our sister's too!"

"Everyone thought you were dead!" Kuina justified. "They still probably do!"

"No one even tried!"

She glanced over at him, saw that he was looking back at her now, fists clenched at his sides. It almost seemed like he was accusing her too, and maybe he was.

Something about that didn't sit right when she thought back to the Queen, to how reserved she'd been, how closed and lonely. She'd lost her entire family, and the Elders had placed far too much responsibility on her shoulders. To be a beacon of hope and peace for their people.

She and Zoro had trained to _protect_ the Queen, even at a young age….to keep her safe, to keep her from the plight of her brothers...

"You were hardly a prisoner, Ichiji," Kuina muttered, expressing the bitterness that had plagued her upon discovering their true living arrangements at Headquarters. Alone, but taken care of, as if they were gifts to the world. They'd been fine, and yet Zoro wasn't, as strong as he'd been...

"The M.A.R.I.N.E.S. treated you great," she said. "They gave you whatever you wanted - stopped their testing whenever you asked."

"Because they knew to respect royalty!"

"You wouldn't have even known you were royalty if I hadn't told you!"

She hadn't intended the outburst, but dammit, it was _frustrating_ when they'd been over this countless times. She didn't know why the brothers insisted on living this delusion, that they had more worth or importance than anyone else. Even as a coping mechanism….it was times like this that Kuina wondered if the three had thoroughly convinced themselves of such…

Ichiji was staring at her again, his brows furrowed over his sunglasses and a deep frown on his face.

"You don't trust us, do you…" he said flatly, no hurt in his tone, merely dry realization.

Kuina growled, baring teeth, and looked away, glaring at the rocks below.

Was that true…?

With a sense of reluctance, she found it might be….

She closed her eyes for a moment. When she spoke again, her voice was quiet.

"For as long as you've been alive, you've never truly known what our colony went through," she murmured, choosing her words carefully. "When I found the three of you, I thought - maybe we could understand each other. That we had similar plights. But that wasn't the case. You haven't known the same hardships. You haven't had the life you knew torn away from you. You haven't _loved_ and lost."

She shook her head slightly.

"I know it's not your fault either. But I need to know you'll be on my side. All of you. Those two idiots listen to you….so please."

Eyes she brought back to Ichiji, who swam slowly now, his tail moving almost in slow motion. His features were tense, and though she couldn't see his eyes, she could almost assume there was a far-away look there. She wasn't sure she'd ever seen him that lost in thought.

"We thought we were humans until you came," he murmured, and her own brow furrowed at his pensive tone. "They told us we were born different, born better, so they kept us away, kept us safe. And then _you_ got dropped in and turned all that upside-down…"

After a second, he chuckled humorlessly.

"Huh. Maybe us and the human one aren't that different after all."

Kuina didn't know how to react, unsure what his intent was with opening up like that, again slyly directing bitterness her way...

"I told you we'd lay low," he continued, his eyes having focused, his tail flicking faster as if he'd suddenly snapped out of a trance. "And we will. For now."

He looked right at her then, and his words rose her hackles.

"But the fact remains that we come from very different worlds, Kuina. We always have. And common heritage doesn't change that…"

With that, he swished his tail and dove down to join his brothers, who'd trailed behind, the two of them having a lifting contest below with boulders nearly their own full size.

Kuina slowed and watched the three of them, not liking the worry that filled her chest.

* * *

"So...you're the Queen? Cushy job," Sanji muttered as they swam down the hall, grinning when his sister rolled her eyes. He was beginning to like getting a rise out of her, almost as much as with Zoro, the banter natural and light.

"You're thinking like a human," she scolded, opening a door and poking her head in. Seeing no sign of Zoro, she pulled her head back out. "It's different here. I'm merely a leader. Primarily a historian. You met Dr. Nico? I've been working with her to compile our history."

She tried the next door down, only to find that room empty as well, yet another unused meeting room that lay prey to the onslaught of barnacles slowly creeping their way onto every surface.

"Ugh, that idiot…" Reiju hissed quietly. "I told him to wait outside. Outside the _door_ , not outside the entire _ship_. I swear… And yet, he lands himself on _your boat_ of all places."

Something about the way she bitched….it reminded Sanji of himself, and while maybe that would have been fascinating, she was bitching about _Zoro_.

And it was stupid, but he actually felt a little annoyed. Her tone was different than Perona's had been, exasperated, yes….but almost fond, in a way. Maybe that was just her voice, much calmer, less shrill, but Sanji felt a pang of undeniable jealousy. He didn't think she and Zoro were an _item_ , no. But just the thought that she no doubt knew the idiot much better than he did….

"You and Zoro seem to know each other well..." he mused, trying to keep his voice casual.

Reiju shrugged, her hair twirling gently away from her face when she looked at him.

"He's part of our defensive force," she replied. "Quite the asset-"

Sanji's entirely skeptical snort interrupted her.

Reiju quirked a brow at him as they neared the end of the hall, which branched off in two separate directions, the large porthole on the wall affording him a view of the trench that he'd nearly forgotten rose up on either side of them outside.

"You haven't seen him take down ten barracudas on his own," his sister insisted, just as, through that very same window, a tuft of green algae sprouted up, atop a grumpy-looking face that peered in with a confused frown.

Zoro's eyebrows shot up though when he saw the two heading towards him, and he quickly thumped a fist into the window. How the fuck had he even gotten out there? The window was latched from the inside.

Reiju dropped her head into her hand, turned to Sanji to say, "What did I tell you," before moving over to unlatch the window.

Immediately, Zoro shoved himself through, broad shoulders nearly getting stuck until he pulled back, changed his angle, then came squeezing in with a grimace and a tornado of bubbles behind him.

Sanji wasn't sure why, but he reached out automatically to grab him - help him? - hands lingering on Zoro's shoulders for a few moments, even after he was fully situated in the hallway opposite them.

"Shut up," Zoro said to him instantly, leading Sanji to realize his mouth had already opened, poised to insult him.

He snapped it shut with a growl and a smug look from Zoro.

The merman reached out to pat Sanji on the head as if he was some kind of vicious pet, which only resulted in a sharp elbow to his stomach, one that sent him doubling over with a grunt, Sanji stealing his smirk and slapping it on his own face.

Reiju watched as Zoro scowled, then lunged out to grab Sanji in a headlock, the blond scrabbling at his head with nails in turn, both beginning to squabble like a pair of guppies.

Admittedly, she'd never seen this from Zoro before. Sure, he bitched and moaned about plenty of things, but he was normally rather serious, a constant dangerous glint in his eye that meant he was always looking for a threat, no matter where he went.

Particularly to her, he showed respect. She would have assumed the same would be the case for her younger brother, also royalty, technically, but clearly that was not the case. To see him take part in such childish theatrics was surprising, to say the least.

She watched quietly, resting her chin in the palm of her hand, only clearing her throat after a minute, the two comically looking up mid-scuffle.

" _You got him into this mess, Zoro,"_ she muttered in her own language. " _So I expect you to keep him safe."_ Of course, she trusted the merman, as idiotic as he could be, especially around her brother, it seemed.

" _You think I don't know that already?"_ Zoro grumbled in return, shoving Sanji off him like the _blond_ had been the one to attack first. " _Are you gonna tell everyone he's back…?"_

Reiju frowned, flicking to Sanji, who glared at Zoro for a minute longer before pushing past his shoulder to examine the window he'd come in through.

" _I haven't decided yet…."_ she replied, as Zoro lifted the tip of his caudal fin to jab at Sanji's side. _"Give him a tour. See how he gets on with the others…."_

" _Don't think there's gonna be a problem,"_ Zoro answered, catching Sanji's tail fin in his hand without looking when the blond tried to whip him back. _"He already met Johnny, Yosaku, and Perona. He's, like, annoyingly personable…"_

Before Reiju could reply, and before Zoro could fucking annoy him anymore, Sanji spoke up.

"Okay, how long do you expect me to pretend to be distracted while you two blabber in a different language?"

"Perhaps you should learn ours, little brother," Reiju said matter-of-factly, something that brought a hugely diabolical grin to Zoro's face, much to the blond's irritation.

"I think I'll _have_ to," Sanji muttered, and jabbed a thumb at Zoro. " _This_ one doesn't understand a word I say."

Zoro's grin fell off his face almost as quickly as it had appeared.

"Let's go," the merman grumbled, grabbing Sanji's wrist and giving a tug hard enough to nearly wrench his arm from its socket.

He was doing a good job of dragging Sanji down the hall, off towards the stairway down which they'd first descended, when Reiju reached out a slender hand to touch Sanji's arm, something that also made Zoro stop when he saw the rather serious look on her face.

He let go of Sanji like a boy scolded and backed off a tail-length. He lingered before finally deciding to continue on down the hallway to wait for Sanji at the foot of the stairs.

Reiju didn't say anything for a long moment, but her silence was enough to have Sanji quiet as well, his features relaxing a bit as he waited, sensing she had something to say, her eyes roving over his face curiously.

"You look like her," she eventually said as soon as Zoro was out of earshot, and when he tilted his head slightly in confusion, she added, "Like Mother…" A slight smile then, almost wistful. "If you want to know more about her, I suggest you ask your human father. Apparently they were good friends."

Sanji's eyes widened in surprise, a strange, slightly hurt feeling fluttering in his chest at the news.

"Friends?" he stuttered quietly, then scoffed, unable to help it. "The geezer had a friend?"

For the first time, she actually smiled properly, seemed genuinely amused, enough that the mirth reached her eyes, lifted another layer of mystique from her visage.

Again, she regarded him, but there was far more warmth there. Sanji felt it.

"Somehow," she replied. "'Nice meeting you' sounds strange."

Sanji let out a dry laugh, still a little stunned.

"I…..yeah…..little bit, huh," he managed. "But….'see you around, sis' is weird too…"

Her smile broadened even further, a youthful softness touching her features.

"Yeah. Don't ever say that to me," she warned, and he couldn't help but chuckle too, a genuine one this time.

"Noted," he said, smirking. Then he bowed low. "Your Majesty."

She rolled her eyes, lifted her tail to nudge him towards the stairs as well.

He moved off down the hall with a smile and a little wave before he was right back to bitching out loud, something about the mosshead not swimming off on his own again like a lost child.

She hoped she'd see him again. But no, hope wasn't necessary because she _would_ , surely. And despite the risks, maybe that wasn't such a bad thing.

She no longer feel quite as alone.

* * *

 _ **O.H.A.R.A. - West Blue**_

* * *

"Oh, look, Chopper! I spy a coming boat in the distance! Even though I'm nearly blind~ Yohohoho~"

The young intern glanced up from his scrubbing, peering over the boat's railing to see, indeed, a medium-sized white research vessel cruising through the waters, its heading pointed directly towards where he and Dr. Brook now sat, cleaning out a few transport tanks on the deck of one of O.H.A.R.A.'s very own moored vessels.

There was nothing off about the scene…..or at least, there wouldn't have been had all their boats not been already accounted for at the dock…

Not to mention….

Chopper lifted his sunglasses up, nestling them in his curly mass of hair to squint through the sunlight at the coming ship.

And sure enough, emblazoned along the side was a very familiar logo.

"Brook! _Brook!_ "he screeched, automatically whipping his sudsy scrubbing sponge at the man beside him. "That's a M.A.R.I.N.E.S. ship! What do we do?"

Naturally, being the older, more experienced one of the two, the thin Dr. Brook let loose a high-pitched scream.

"AAAAHHHHH!" he cried, throwing up arms, his own thick black curls flouncing in the wind as he flailed. "What do we do?!"

"I don't know! I just asked you that!" Chopper yelped, turning back to look fearfully at the ship, raising a hand to bite at nails, a nervous habit he'd been trying to break but had a rather hard time of when Franky and Robin kept insisting they watch scary movies in their downtime, and Nami threatened him with more debt every time he didn't consult her first before rotating the seal enclosures.

"We should warn the others!" Dr. Brook finally exclaimed. "Do we have any mer-guests at the moment?"

"I-I don't think so," Chopper stammered. "But-" His stomach dropped, remembering just what significant events had taken place at O.H.A.R.A. not three days ago. "Oh no, what if something happened to Zoro! He took the bracelet and-!"

Thankfully, before too much panic could overwhelm him, a bony hand came down on his shoulder, skin dark against the white of his T-shirt.

"Let's not jump to conclusions, Chopper," Dr. Brook hummed comfortingly, giving his shoulder a squeeze. "Perhaps they're simply passing by."

"They're headed right towards us!" Chopper squeaked.

And indeed, the boat had nearly finished its approach, looming larger than the small vessel the two observers were parked on, the two unable to do much but watch as it began to turn wide, in preparation for mooring directly across from their boat alongside the open side of the dock.

There were humans visible on the boat, blotchy forms behind the tinted windows of the control room, but when one of them slid open and an intimidating man poked his head out, not one but two cigars clenched between his teeth, Chopper gasped.

 _"That's Dr. Sakazuki,"_ he whispered to Brook, covering his mouth as if the man would overhear. _"I've heard of him. Really big guy….always smoking…."_

 _"Maybe if we stay very still, he won't see us,"_ Brook suggested, just before the man in the approaching boat called out to them over the purr of his boat's engine, "This is Smoker from M.A.R.I.N.E.S. HQ! I'm parkin' her here!"

And without waiting for an answer or a reply from the two wide-eyed men still crouched, elbow-deep in soapy water, he slowed the boat and steered it into the free spot rather expertly, its hull bumping ever so slightly against the wood of the dock.

Brook and Chopper hadn't moved, even as the boat cut its engine, two other men appearing from inside the cabin, one with pink hair pushed back by a folded bandana, and another lanky blond, both of whom began securing the boat to the dock.

It was silent for a moment, save for the scurrying of the two men, before Brook asked, " _Do you think he saw us?"_

"Oh, Captain Smoker! It's been quite a long time! To what do we owe the pleasure~?"

A smooth voice and a pair of footsteps on the sturdy dock, and it was Robin, dressed not in her usual wet suit, but a simple black polo dress and sandals, her long hair pulled up in a neat ponytail. She shot a sly glance at Chopper and Brook, still trying to camouflage themselves as best they could.

"I was referred to you by Dr. Red," Smoker said, stubbing out his cigars on the edge of the rail before tossing the butts into a bin resting under a bench on the deck. He unhooked a latch on the railing and swung open a small section so he could climb out onto the dock, boots landing heavily. "If you'll recall, I served an internship under him many years ago."

"How could I forget," Robin replied with a chuckle, shaking his hand firmly when he offered it.

Behind him, Tashigi emerged as well, looking distracted as she glanced around at her surroundings, nearly causing her to fall flat on her face when her foot caught on the lip of the boat.

"This is Tashigi," Smoker grumbled, hooking a thumb over his shoulder, the woman quickly righting herself and hurrying over to shake Robin's hand as well. "Tashigi, Dr. Nico. We got two other kids from HQ here too."

Coby and Helmeppo gave small, slightly bewildered waves from their positions securing ropes at the stern.

"Please, call me Robin," the woman replied with a smile. "I'm surprised to see you back from the Grand Line so soon. I take it the research is-"

"There's been a security breach at HQ," Smoker interrupted swiftly, and her pleasant expression fell immediately. "Three mermen and a mermaid have escaped. We believe they plan to rejoin the colony."

Robin stared, eyes like ice, now cool and calculating. Chopper and Brook both paled.

A long moment stretched of silence. Even the calls of the seagulls overhead seemed to cease.

"You mean to tell me," Robin finally breathed, voice quiet and dangerous. "They've still had live prisoners….?"

Smoker stared right back, undeterred by the tension of the moment.

"Were you not aware?" he asked, ignoring the nervous way Tashigi shifted beside him, clearly struggling not to wring hands.

"I'm afraid not," Robin replied, willing back the flash of emotion that had nearly shown through on her features. She clenched her jaw tight, remaining stoic. "Though this explains why they've been quiet..."

The warmth in her greeting was gone. And with it, the open trust she'd had for a man so highly-regarded by Dr. Red.

"And why have you come to us?" she wondered, despite hearing his reason a minute ago.

"A referral from Dr. Red, like I said," Smoker repeated gruffly. "He wants no part in negotiations with the M.A.R.I.N.E.S. He seemed to think your organization would be willing to help instead."

"If by help, you mean _protect_ what needs to be protected," Robin shot back immediately, fiercely, almost daring him to say otherwise. Daring him to reveal an unjust motive.

But he merely let out a breath through his nose, gave a sharp, focused nod.

"Precisely," he said.

Beside him, Tashigi broke into a relieved smile almost immediately, Coby and Helmeppo both sharing a disbelieving look between them.

Robin quirked a brow, noting the trio's reactions.

It did little to dispel her worries in that moment. But Smoker still stood there, calm, steadfast, waiting for her reply.

"Please join me inside," was all she said, and gestured for them to follow her back towards the entrance, dwarfed by the towering cliffs above them.

* * *

Sanji hadn't smiled once in the hour Zoro spent leading him through the labyrinthine halls of _Noah,_ to the most interesting places Zoro could think of on the ship - the old shuffleboard rooms, the swimming pool with its detailed mosaics. Even the lavish bars that had no doubt been used for that drinking thing humans did, where they drank that special brew and got fucked up and silly.

Maybe it was all too familiar to Sanji, human stuff. Maybe he was boring him, and that was why he hadn't smiled.

Well, he sort of had, but his attempts were half-hearted, not the genuine grins or looks of complete wonder that he'd exhibited when they'd first arrived. Sure, _maybe_ Zoro had gotten them turned around once. Even he could admit that. The place was damn confusing after all.

But the sparkle had left Sanji's blue eyes, even as they passed through the dining hall, vast and ghostly with its countless empty tables, old tablecloths billowing in the water. He didn't know why, but he'd had a hunch Sanji might find it intriguing.

And yet, all the response the blond gave him was a simple, quiet, "Whoa," that escaped him as he stared somewhat despondently at that open space, fingers brushing over the back of a chair that matched his wooden reaction.

Zoro felt his heartbeat speed up, because this space was actually kind of special.

He and Kuina had come here when they were young, mainly because it was a good space to train, large and sprawling. On days the currents had been too strong outside, they'd played in here, clacking together weird human weapons they'd found, and dammit, every time he even _looked_ at one of these tables or chairs, he remembered Kuina hurling one at him to deter him. He remembered her playful grin and the fierce cry of her voice as she attacked.

And yet Sanji was emotionless. After _everything_ he'd seen and learned, he was withdrawing into himself. Because yes, Zoro recognized it. It was a way he himself had come to cope with things. He took the burden alone.

But for some reason, when it was someone else, when it was _Sanji_ , it frustrated him, enough that he growled and rounded on the blond, cornering him against the long wall of windows that filtered in just enough sunlight from far above to cast an unearthly blue tint over Sanji's features.

"What wrong?" he grumbled, one hand slamming down on the window pane beside Sanji's head. He wasn't letting Sanji dodge this.

Did he not _like_ it here? Was he having any sort of second thoughts regarding his feelings towards the merpeople? Zoro trusted him, but for all of this to fall apart now would be unthinkable.

Sanji just lifted dull eyes to Zoro's face though in a deadpan stare.

"What wrong?" he repeated skeptically, in a dumb imitation of Zoro's gravelly tone and incorrect grammar.

"Argh - _what's_ \- wrong," Zoro amended with growing annoyance. He wasn't in the mood for the blond's jibes.

Sanji scoffed, his hair practically glowing with the light behind him, enough that Zoro had to stop himself from staring and fix his eyes to Sanji's face, serious.

"What do you mean?" the blond asked, gesturing to his surroundings. "I'm here in a fucking underwater luxury palace. I'm a _merman_. I just met my long-lost sister. Nothing's wrong!"

The sarcasm in his voice did nothing to help his words ring true, however, and nor did his eyes, hastily looking away from Zoro, both brows knit tight over them, Zoro saw as he caught a glimpse of Sanji's right eye when his hair floated up a bit.

He wasn't good at picking up on tone in the human language. It was sometimes hard to tell when people were messing with him or not, but he understood Sanji then, enough that he looked away for a second, focusing on Sanji's collarbone for a moment before bringing a troubled gaze back to Sanji's face.

"Queen….tell you….all?" he asked slowly, and when Sanji's jaw muscle twitched again, Zoro knew the answer, even before he nodded jerkily and replied, "...Yes…"

Zoro closed his eyes for a moment, then lowered his hand from the window and backed up a bit to float before Sanji without looming.

"So what's wrong…?" he asked, knowing what had to be, but wanting to see if the blond would open up to him. He was no good at dealing with _feelings_. He couldn't even deal with his own, but with Sanji hovering there, looking damn upset...maybe his human instincts kicked in a little.

Sanji made a movement of shoulders, chest rising a bit as if to breathe before he seemed to remember where he was when nothing but water flowed into his mouth.

He made a small disgruntled noise before sliding down the window to sit on the floor, careful not to crush his dorsal fin.

Zoro stared at him for a second before he elected to follow, flipping over to his stomach to float in front of the blond.

"Zoro…" Sanji said after a moment, flicking eyes to the other merman, but then quickly averting them again, a faint flush coloring his cheeks. "I've gone my entire life assuming my birth parents didn't care - or - or _couldn't_ care about me, at the very least. And I - ugh, mosshead, just try to follow along, okay?"

The confused scowl that had come to Zoro's face from Sanji's fancy language only deepened at the blond's snippy tone. But he figured, even if he didn't understand everything Sanji said to him, letting him get his thoughts off his chest might brighten his mood some. So he'd listen. Or try to anyway.

"I've always thought," Sanji was saying. "That they dumped me on a beach, left me to die, when they did the exact opposite! They loved me so much they were willing to do fucking - crazy things to keep me safe! To keep my whole family safe! I just - I've never - I've always tried to accept the fact that they left me, and appreciate what I do have, but - I don't know, it just feels like a new wound's been opened…"

The blond pushed a hand back through his hair, gave Zoro a somewhat helpless shrug.

"And on top of everything, my old man didn't trust me enough to tell me the truth," Sanji went on, voice more pained with this statement than anything else. "He was _friends_ with my mother, I mean what-" He paused, lifting eyes to Zoro's face. "Lost, aren't you. Typical."

Yes, he was. Something about Sanji's parents. Something about keeping him safe. That was about all Zoro got, but it was enough.

He swam closer, Sanji's eyes a magnetic pull, and he reached out to touch him, fingers landing on his jaw for a moment before they took off again and slid through strands of blond, playing gently with the hair that wove around his face, combing it back to get a look at both of his eyes at once again.

No making fun of his eyebrows this time, just touching and taking in Sanji's features, vulnerable, but still trying to remain proud.

Between them, his beads floated up a little too high, obstructing his view. He was about to push them down, but then Sanji's hand lifted, taking a bead delicately between his fingers, stroking gently over the smooth little spheres.

There was a question in his eyes, though he remained quiet, and Zoro found himself answering it before he could justify otherwise.

"Kuina. Her name," he murmured, watching Sanji the whole time. "M.A.R.I.N.E.S. took her too."

Sanji nodded silently, staring at the beads for a moment longer. Then he carefully pushed them back down to press against Zoro's chest, leaving his hand there, the beads beneath them.

"Just like my brothers. And my mom," he said flatly.

Zoro's turn to nod. He took his own hand from Sanji's face and moved it to his chest, to gently slip fingers between the blond's, feeling how smooth his skin was, how well their hands fit together.

"Zoro…." Sanji said, his other hand lifting to the back of Zoro's neck, playing delicately with the ends of his hair. "I keep thinking….what if they didn't die…? The M.A.R.I.N.E.S - they're scientists - they wouldn't kill their experiments. Trust me, I know."

He finally looked Zoro in the eye again, a bit of hope there, but the merman merely lifted the corner of his lips forlornly.

He'd caught Sanji's question, after all. And, of course, he would have liked to believe this. But it had been fifteen years. It was best to move on.

"I...think about…" he replied, trying to find the words in Sanji's language. "But…"

Sanji understood though, and he shook his head, fingers clenching in Zoro's hair ever so slightly.

"Yeah," he muttered. "No use getting our hopes up…"

It fell quiet then, just the faint rush of the water around them, the two of them alone, with the daylight above beginning to wane, the sun's rays dancing, casting cool shadows over the blond's face, his pale skin bright.

His lips were still so pink though, and Zoro had the urge, suddenly, not to bite, but to do that thing humans did. To press their lips together and - and what? What did they do? He'd seen Franky and Robin do it plenty of times, even seen in some of those movie things they'd shown him. But it wasn't really something _merpeople_ did.

Would Sanji want to? Would he be upset if he tried? Did Sanji even _feel_ the charge between them or what? He'd bitten him…..so maybe...deep down...

There was only one way to find out.

Slowly, Zoro swished his tail to propel him towards Sanji a little closer, close the gap between them.

But the hand at his chest was gently pushing as Sanji started to straighten, rising back up the window behind him and giving Zoro's hand a tug to bring him with him.

"Can you take me home?" Sanji asked quietly, still holding onto Zoro's hand. "I need to talk to my old man…"

Zoro didn't think he'd felt disappointment like that in a long time, and _why?_

Fuck, he didn't know. But the healing bite on his shoulder gave a little throb.

Still, he nodded.

* * *

The journey back to B.A.R.A.T.I.E. hadn't taken nearly as long as the journey to _Noah_ , or at least, so it felt, but it certainly hadn't been as enjoyable.

It was still fascinating, to watch the water change color as the sun sank lower in the sky, see the brilliant pinks and oranges of the sunset begin to fill the reefs and open water with a magical, warm quality that Sanji never wanted to forget.

He didn't want to leave. He wanted to prolong this. He wanted to explore and not have to worry about all that had been told to him that day, all he had discovered about himself and his family that still hurt his brain and twisted in his chest.

He'd come back. He had to. But he shouldn't. Not yet. Not until he found out the full truth from his father.

Part of him worried. This undersea world, _his_ world, incredible as it might have been….he wasn't sure he wanted it to be his _only_ world….and he could only hope whatever his father had to say wouldn't drive him to seek it as such…

They were mostly silent as they swam, Sanji lost in thought, replaying pieces of conversation from the day, Zoro seemingly preoccupied too as he led the way. A few times, Sanji had reached out and told him to change direction, purely by instinct, and he wondered if he had some homing skills of his own in this form because, before long, a poke of his head above the water showed the breakers coming up in the distance, the boats docked at the lab bobbing beyond, the low sunlight glaring off them like beacons.

His dad was back, though the docks were empty.

Dread still managed to fill his stomach.

The approach was safe, no one stalking about outside, so Zoro came right up to the edge of the dock with him, looking a little unsure, a little awkward, but Sanji felt it too. Goodbyes were not his strong suit, and though he'd said it to Zoro once, this time felt…..rather different.

Sanji didn't waste time, merely reached to his wrist and pressed the button on the bracelet to release it before he could stop himself.

He threw arms up onto the dock and pressed his forehead to the wood, closing eyes as he waited for the transformation to start.

It did, with a jolt to his system, warmth tingling through his lower half, up to his chest, the water sloshing beneath him until he suddenly became aware that his tail had split, leaving two legs in its place, the tight material of his shorts once again clinging to his skin.

For a moment, he couldn't fault Zoro as he had to actively remind himself to breathe again too, finally sucking air into his lungs for the first time since that morning.

It was a weird feeling, even though it should have been smooth and natural. He was reminded of when he'd gotten his braces off his teeth when he was in high school. Back to his natural state, but also foreign, after getting used to another form.

He felt Zoro hovering close to him, but he focused on catching his breath, eventually getting enough of a grip that he managed to pull himself up onto the dock, smoothing his wet hair back into order, finger-combing automatically and giving it a shake so he could flop it over his face like usual.

A look around him told him that his clothes, which he'd left on the dock that morning, were gone….not a good sign. His dad had probably found them.

He sighed, an odd sensation after not being able to do it for so long.

There was nothing left to do in that moment other than confront what he didn't want to confront….and that included parting ways with the mosshead.

So he reached out with the bracelet in hand to pass it to Zoro.

"Keep this safe for me, okay…?" he said, waiting until the merman slowly reached up to take it.

Zoro snorted, looking down at the bracelet in his hands. Shit, he'd forgotten the carrying pouch Robin had given him inside Sanji's house. Lacking anywhere else to put it, Zoro clipped it around his necklace.

"Queen said...same thing…" he muttered as he did.

"About the bracelet…?" Sanji asked, and he shook his head, eventually looking up to meet Sanji's eye again.

"No…" he replied. "About you..."

He saw Sanji's eyebrow raise ever so slightly, his lips parting as if to say something, though no words came out. But there was a faint hint of red coming to his cheeks that Zoro found himself fixated on for a long moment.

Dammit, Sanji was a merman. He shouldn't have to leave, not so soon. There was still so much to show him, so much for him to learn. Not to mention….

"But can't - keep safe if - if you're - _there_ …."

Zoro muttered it sulkily, jerking his chin towards the buildings behind Sanji, as if the very structures themselves could swallow Sanji up now that the truth about his past was out.

It had been his idea. His idea to bring Sanji to _Noah_ , and he didn't regret it one bit, but...if they couldn't be together….

Sanji was quiet too, shooting a slow glance back at the building as well, one that was almost disdainful. He knew he had to go back. He had to confront his father, had to start _doing_ something, anything, to prevent what had happened to Zoro's - _his_ \- people. _Fuck_ , it was still so unbelievable.

But thoughts of that bright, blue ocean. The freedom and excitement. The beauty.

And then there was Zoro, who now bobbed there, pouting, and Sanji thought back to that moment on the ship. That moment when he'd seen Zoro so close to him, felt his hand resting perfectly over his own. The moment when he'd panicked, not knowing if they should do this. Not knowing if it could _work_ , or if Zoro even…

Fuck it. After the emotions he'd felt that day, he could deal with whatever this brought.

"Zoro, how do you feel about me?" he asked abruptly, watching when Zoro's dark eyes flicked up to him again, familiar confusion behind his furrowed brow.

"Feel…?" he asked, tilting his head slightly with a frown.

"Yeah, like-" Sanji stuttered, telling himself he needn't feel stupid, or like he was laying himself bare when an even dumber idiot floated before him. One that was endearing as fuck with that look of confusion on his face…

"I just...in the ship. There was a moment," he clarified, unsure if Zoro would know what he was talking about. "Actually there's been a lot of moments… You - I dunno, sometimes you just look at me and-"

Something in Zoro's eyes flashed. Recognition, his mouth dropping open ever so slightly as if he couldn't believe what he was hearing.

He didn't answer right away, but he moved, a flick of his tail pushing him up higher out of the water so he could hover closer to Sanji's face, close enough that the blond could see the small water droplets clinging to his eyelashes, that tiny splash of faint freckles barely visible on his nose.

His lips were inches away, and there was no way he was oblivious.

"You...mean this," Zoro murmured, body rising and falling slightly with every ebb of the sea.

Sanji lost his breath somewhere, the arm he leaned on nearly giving out. He swallowed hard, but eventually managed to reply a mesmerized, "Exactly…"

So he hadn't imagined it. There was something tangible between the two of them, and Zoro felt it too. He didn't know how Zoro perceived it, but he _felt_ it, and that was enough to keep Sanji from feeling too crazy, though the vulnerability was there full force.

"Want to," Zoro was saying, and his gaze had fallen to Sanji's lips, studying there fixedly as if seeing them for the first time. "Do - human thing."

Sanji watched Zoro, his hand already itching to reach out and touch his slick skin, slide fingers into his hair.

"Human - thing?" he stuttered, mostly to fill the silence.

Zoro nodded, lifted himself until their lips almost met.

"You?" the merman asked.

Sanji's reply was quick and insistent.

"Fuck yes, are you only _just_ getting that now, idiot?"

Zoro grinned broadly, jagged teeth on display.

And then, with a flick of his tail, he rose up to finally crash lips into Sanji's, his hand coming to the nape of Sanji's neck for leverage.

Sanji's response was instant, his mouth opening hungrily, not even _trying_ to keep it innocent for Zoro's sake when he so very much wanted this, had imagined this ever since first laying eyes on Zoro.

If Zoro didn't know how to kiss, if merpeople did or didn't do this, fuck if Sanji knew, because right then, he was doing a fucking fantastic job, lips moving, if not with grace, than with fluid ease, his tongue slipping against the blond's to match his bold rhythm.

He was careful though, mindful of his sharp teeth, Sanji realized, when the tiny nips he snuck to Sanji's swollen lips were but gentle scrapes, and the blond had to wonder how difficult it was for Zoro to hold back, knowing that he'd felt the same primal instincts that day.

Sanji kept one hand firmly planted on the dock for balance, but the other he brought to Zoro's face, thumb stroking tender circles, hot breaths panting over the merman's lips in the brief seconds he was able to break away.

None came from the merman, unsurprisingly, and though his stamina was to be envied, not needing air, _Sanji_ most certainly did. Eventually, he had no choice but to pull back, staying right there with his forehead pressed to Zoro's, but heavy puffs of air huffing from him as Zoro tilted his head to nibble along his jaw before he seemed to remember himself and stopped as well.

 _"Holy shit,"_ Sanji whispered between breaths, and he tried not to grin at Zoro's snicker.

"What?" the merman asked, somehow managing to sound just as breathless and sated.

Sanji let his eyes flicker open, pulling back an inch to remind himself that he'd indeed just kissed a merman, that Zoro was very much a mythological creature, and he was very much not in a fairy tale.

"Nothing," Sanji muttered with a quiet chuckle. "I'm just - expecting a singing crab to be lurking around…."

Zoro understood absolutely none of his answer, but he didn't care, far too preoccupied with Sanji's lidded eyes, how warm his face felt when he nuzzled his nose against the man's cheek.

"Again?" he rumbled, already sneaking a hand up to the back of Sanji's neck, his other coming to his necklace, and the bracelet clipped there.

"What?" Sanji huffed. "Have you actually seen a singing cra-mmph!"

Zoro's lips met his again, but this time, the merman gave a forceful tug to the back of Sanji's neck, making him lose his balance and dragging him clear off the dock into the water below.

It happened fast, the bracelet clamping onto his wrist, the transformation, Zoro's lips on his the entire time, but then, Sanji didn't _need_ air anymore and he felt that flood of instinctive dominance and aggression again.

His hands slid over Zoro's smooth chest, nails raking along until he'd looped arms over the merman's shoulders, Zoro's palms struggling to feel all of Sanji's back as well.

He felt the ocean rush around him as they kissed, a feeling that made him feel powerful, like he'd left his body entirely and the two of them were indeed part of the water itself.

He heard the soft growls and noises the merman made in the back of his throat, and was certain but uncaring that some escaped him as well. After all, he'd never felt this. It had never been like this. It had never been this effortless, this _endless_ , with nothing to stop them save for their own hearts beating out of their chests.

Fuck, he wanted this, wanted him, wanted to drag _Zoro_ back above water, slap the bracelet on him and keep him forever, but he couldn't. As much as he wanted to, he couldn't, so he mustered all his might to pull off the merman's lips.

"Zoro," Sanji murmured, hands threaded in the merman's hair, his eyes closed as Zoro's lips moved over his skin, teeth scraping and nibbling gently at the juncture of neck and throat. Fuck, it felt good, in a way he hadn't felt in _so_ long. "Zoro, I still have to go."

Zoro didn't let up, dragged teeth over his skin with barely-restrained hunger.

"Don't," he said, and his voice was so low and husky that Sanji's heart skipped a beat.

"I wanna stay, trust me. Fuck."

So many regrets, cutting this moment short. More regret than he'd felt the whole day, and wasn't that fucked up.

A hand fisted in Zoro's hair, and he hurriedly kissed him again, one last time before pushing off him and flicking his tail to swim to the surface, where he removed the bracelet once more.

His heart was still pounding and breaths now panted as if he'd sprinted a marathon.

But he shoved the bracelet back at Zoro, who'd popped up as well.

As soon as Zoro took it, Sanji pulled him close for one more kiss before he turned and climbed up onto the dock once more.

The same process of wringing his hair out, giving it a shake, and he made the mistake of looking at Zoro a final time.

The merman had rested elbows on the dock, pushed himself up a bit in an attempt to be as close to Sanji as he could until the last possible moment.

Sanji looked at him, at how the sunset reflected so much in his eyes, a burning want, but also a smitten devotion that flickered through amber irises.

He'd been about to get up, but then hissed out a frustrated, " _Fuck,"_ and dove in for one last kiss that drew a broad grin onto Zoro's face.

It was perhaps the dumbest, most lopsided grin Sanji had seen from the merman yet, and Sanji knew the one that came to his own face was likely very similar.

Still, he forced himself to stand, a tiny bit wobbly on his feet for a second, but his body quickly adjusted to being human again as he walked off towards the building, muttering to himself the whole way, curse-filled mutterings of disbelief.

That shit had happened. That shit had _actually happened._

And as he reached the doors, and turned around to look over his shoulder, indeed there was still a merman watching him.

"When come back?" Zoro called after him, and Sanji's grin turned even dopier.

"Tomorrow!" he answered without thinking. "I'll meet you out here."

Zoro nodded far too eagerly, and Sanji laughed.

Yeah. Regardless of what happened with his dad. Regardless of anything. He had fucking _this_ to come back to.

And how amazingly ridiculous was that?

* * *

By the time Zeff heard the front door to the bungalow swing open, the wet slap of flip-flops against the wood floor, he'd composed himself, wiped away any tension or anger.

But only from his face. And he knew the boy would likely be terrified when he turned slowly from his place in his arm chair, muting the TV and leveling the young blond with his hard gaze.

The boy was wet, hair ruffled, most likely courtesy of a towel draped over his neck and shoulders, looking a little dazed, a little bewildered.

Zeff's blood boiled and his stomach clenched at the sight.

"And where the hell have you been?" he growled.


	9. Resurfacing

So Sanji was a merman. The day had really happened. He'd really transformed and he'd really dove deeper into the sea than he ever had before, witnessing an entire fantastical world that had apparently existed just beyond humans' reach for longer than they probably knew.

It should have been a dream.

But he'd seen science in action, science he didn't yet understand and was hungry to learn about, learn every secret he possibly could as if it would slip away from him if he didn't.

He'd learned about his family, his birth family, five of whom were lost, ripping open the small hole that had always persisted in his heart, despite how happy he was living with his old man.

Suddenly, things made sense, or he thought they did, his fascination and connection to water, that nostalgic feeling he got looking out over an open ocean, or his desire to spend hours underwater, escape there if he could.

He'd never had that life, never in his wildest dreams imagined he _could_ have it. But now, amazingly, incredibly, impossibly….it was within his grasp.

And yet, despite the overwhelming amount of things he'd experienced over the past few days, despite how groundbreaking everything he'd seen was….how much it could change the _world_ ….

All he could think about was Zoro, and his _fucking_ lips, and his _fucking_ smile, his voice and the way his hands had felt sliding over his skin, the feel of the merman's chest pressing against his, and how quickly, alarmingly so, his initial attraction had begun to blossom into something more, an attachment he hadn't felt before, not even with Ace.

It shouldn't have made sense. Ace was one of the kindest, most understanding, and most patient people he knew. It should have been anyone's dream to be with him.

Zoro, on the other hand, was annoying, slow as hell, and stubborn to boot.

But his sincerity, and the intensity with which he _lived_ ….the challenge he provided Sanji just by existing. There was something new and incredibly attractive about that.

Not to mention he understood…. Even in the short time they'd known each other, he'd proven he understood Sanji perhaps more deeply than anyone.

When Sanji had first come to terms with his attraction to men, it had terrified him. Even with Ace, it had been scary, embarrassing as he figured himself out.

With Zoro it was…..natural.

Which was ridiculous because he was a fucking _merman_ , but...

Well, maybe that was the point. He wasn't human, and thereby held none of the judgment humans so liked to bestow. Zoro didn't care about any of that shit and-

"And where the hell have you been?"

Sanji blinked, stolen from his thoughts, and he realized he'd made it back to his and Zeff's bungalow, almost in a trance, because he couldn't exactly remember grabbing a towel, slipping into a spare pair of flip-flops.

But he was standing in the doorway, and his father was staring him down, nestled deeply in his cushy armchair, in one of his favorite knit sweaters, but managing to look the part of a mob boss rather than a kindly old grandpa.

His dad was sitting there, demanding an answer with his glare alone, and Sanji had about as much hope avoiding the truth as he did convincing himself he was completely straight.

It didn't matter. He'd come back here with the intention of confronting his dad, of finding out, once and for all, why he'd kept all this from him. Why he hadn't said a fucking _word_ his entire life. Why he'd been _friends_ with his mother and still let Sanji believe she'd dumped him without a care.

He'd also intended to play it cool, or at least try, but thinking back to the look on his sister's face, that empty, alone look when she'd recounted their family's plight….

"Why didn't you tell me?" Sanji asked immediately, stepping forward into the room with renewed conviction, closing the door behind him.

He was met with silence.

And that silence infuriated him.

He was _sure_ his dad knew what he was talking about. Maybe they hadn't talked about it much since that day at O.H.A.R.A., but surely his dad knew that it hadn't left his mind. Not for a second.

"Answer me, old man!" he barked, feeling his chest shudder with the outburst. He let the anger bubble up within him, hoping it would cover the fragile frustration and sorrow.

"Why didn't you tell me?!" Sanji asked again, voice rising. "You knew everything! You knew all along - you knew-!"

"Watch your tone, brat."

" _Why. Didn't. You tell me."_

It was a demand now, and Sanji would _not_ tolerate a stupid answer.

"It's not safe," Zeff growled.

A stupid answer just like that.

"What's not safe!" Sanji cried, his voice childlike in his desperation, threatening to break on him. "Quit _saying_ that! It's-!"

"Where did you go today, brat?" Zeff implored, and Sanji quickly found himself slipping back into surly teenage habits when he groaned with frustration and reached up to clench a fist in his hair.

"None of your business, geezer! I did the work you told me! _Stop_ changing the subject!"

He wasn't _stupid_ , for fuck's sake, but when his dad sat there calmly in his chair, passing silent judgment, he felt it, and it was something his dad hadn't made him feel for a long time. He'd thought his dad respected him, that he was old enough and experienced enough to have his father's trust, but here he was being treated like a child again.

"Where did you go?" his father asked yet another time. "Why were your things out by the water?"

Discomfort bubbled within Sanji's chest. He knew he wouldn't be able to keep the secret, and while it wasn't certain whether his father knew of the bracelet, he had a feeling any answer that had to do with merpeople would elicit a bad response.

Sanji brought a hand to his wrist, fingers rubbing there subconsciously.

"Don't turn this on _me…"_ he muttered bitterly. Not when he still deserved answers, not when _he_ was the one who'd discovered he was born to _merfolk_ …

Zeff's eyes fell beneath bushy eyebrows to Sanji's wrist, his heartbeat a dull thud in his chest.

He'd always thought...that one day he'd have to deal with all this. That one day he'd have to own up for the choices of a younger, more cowardly version of himself that he didn't like to admit existed.

But he hadn't imagined that those choices might result in the loss of the son he'd worked so hard to protect…

He wasn't sure how much Sanji knew, beyond what was revealed at O.H.A.R.A., but the pain in his son's voice….it had been true, not merely the sulking of someone let in on a scientific secret far too late.

"Who gave you the bracelet?" Zeff asked, determined to see if his hunch was right, dread striking him sharply when he saw a flash of panic in the boy's eyes, the quick diverting of his gaze.

"Was it Robin Nico?" Zeff pressed, anger beginning to rise within him at the thought. The woman had assured him she'd keep that bracelet under wraps, and he'd assumed she'd uphold that, even after their meeting earlier that week.

Now, Sanji wasn't answering him, the blond glaring steadily at the floor, his jaw clenching along with his fist, chest lifting in measured breaths that Zeff recognized as a way to calm himself, one that wasn't working.

"Who?" Zeff growled. "Did you actually-?"

Sanji couldn't help it. He exploded, unable to think about anything save for the fact that his own father had lied to him for so long, that he'd lost nearly his entire family and never known, left his own sister to lead a lonely life for years, while he lived in peaceful obliviousness in a world that didn't even know of her existence.

"Zoro brought it!" Sanji cried. "And yes, I went with him!"

His voice broke and he couldn't stop it, tears having come to his eyes at some point, spilling hot trails down his cheeks, teeth bared in a tight grimace as everything he'd held back all day rushed him, in the presence of perhaps the only person who'd ever seen him cry.

"You didn't tell me I was one of them!" he exclaimed shakily. "You didn't tell me about my family! About how my parents died, about my _brothers!_ I met my _sister_ today! You knew my _mother!"_

A silence befell them, heavier than perhaps any they'd ever shared. It was anxious and it was angry, but most of all, it was _painful._

It was physically painful to stand there and look at his father, feeling as betrayed as he did, throat and eyes burning as they bore into Zeff, who continued to sit there firmly, both feet planted on the ground.

He didn't like the weary look that came to his dad's eye, not when there was always fire, always subtle endearment.

Now, he looked twenty years older, face drawn and shadowed in the fading ambient light.

"You could've trusted me, dammit…" Sanji shuddered out, voice barely above a whisper. "You could've told me the truth. You tell me everything - why wouldn't you?"

Sanji's heart beat hard in his chest, a sickening anticipation filling him, along with a deep fear, fear that Zeff would continue to conceal the truth, that not even his raw emotion would be enough to coax the answers he so desperately wanted from his stubborn father.

He stood there, a tremble running through him that wasn't helped by the cool air conditioning, the vent's faint white noise doing nothing to make the silence more bearable.

Zeff closed his eyes for a moment.

But when he opened them, it was to look directly into Sanji's.

"Because the M.A.R.I.N.E.S. would've taken you," he said, fists curling over the arms of his chair. "They tried when you were young. But they agreed to leave you alone on two conditions."

It was stupid just how quickly Sanji was made to feel foolish for his actions, despite believing wholeheartedly his father should have told him. A hand lifted to hastily scrub at his wet cheeks, the tightness in his chest quickly replaced by an embarrassed fluttering.

He needn't have felt that way, he knew, but there was something about the air of defeat in his father's voice….and the fact that maybe there _was_ more to the story...

"What two conditions?" he choked out, clearing his throat and trying desperately to get himself together, stop his pathetic sniffling.

"If I raised you as a normal human, told you nothing of your world," Zeff answered, though he paused as if gathering conviction for the second condition. "And if I didn't report their research to the government - to the _Navy_. If I didn't report….what they took…"

Sanji's heart clenched anew, fresh tears threatening to spill. Not even the logic behind Zeff's answer was enough to appease him.

"So you knew… You knew what they were doing-" he breathed, voice rising. " _Kidnapping_ merpeople? Experiments? You _knew_ and you still did nothing?!"

"To protect you, brat, don't you see?! Your mother turned herself in to them to keep you safe! And I wasn't about to-"

"So what! This is bigger than just me! Come on, old man, you know that!" Sanji interrupted, the most bitter thought of all filling his mind. "You could've saved her!"

Suddenly, Zeff sprang from his chair with alarming speed, as if to pounce, the older man crossing to Sanji in a few short strides, matching his height and entering his space with a piercing glare.

And yet his voice was dangerously quiet.

" _You think I don't agonize over that…_ " he gritted out, and Sanji was rather stunned to hear the slightest hint of a tremble to his normally strong tone, a quavering finality to his words, particularly when he insisted, " _But your mother wanted you safe."_

Sanji gave a frustrated growl.

How could he argue with that, after all? Even if he still believed otherwise….even if, in his mind, the decision should have been easy for his father… Would it truly have been better for the old man to risk his safety and go back on his mother's trust, when the M.A.R.I.N.E.S. clearly weren't trustworthy themselves?

Fuck if he knew, in that moment, his thoughts spinning, and the emotions overwhelming and exhausting him, his body feeling physically drained standing there opposite his father, who still managed to stand steadily before him.

Zeff seemed to take his son's silence as some form of concession, because, after a long minute, he said firmly, "I don't want you going back. I learned some disturbing news today and..."

And he'd been worried….worried for his eggplant's safety, for the first time in a long time.

His father trailed off quietly, and yet, Sanji felt a jolt of panic shoot through him after his first sentence alone. Exhausted and uncertain he may have been, but there was one thing he knew for sure.

"You don't want me going back?!" Sanji cried with defiance. "I'm going back! I have to now! I'm - I'm their - their prince and-!"

"Sanji!" Zeff interrupted fiercely, with more power than he'd used yet, and with his son's name on top of everything. It took Sanji right back to moments in his childhood, moments when he _knew_ his father was serious, truly genuine in whatever emotion spouted his name.

And now, with the anger in Zeff's eyes, Sanji knew he'd succeeded in tipping his father over the edge.

Spiteful as it was, the less mature side of him thought he deserved it.

"Until this blows over, you will obey me. If you get hurt..." Zeff continued, gaze working hard to intimidate his stoic son.

A gaze that also worked hard to conceal the true fuel behind his order, the downright fear he had for Sanji. The fact that he did not want to lose this boy who _was_ his son, no matter where he'd come from.

Maybe he was born to merfolk, but they hadn't raised him. They hadn't been there through his ups and downs. They hadn't held him when he was young and confused, wondering why the children at school teased him for being adopted. They hadn't seen him grow into the headstrong, intelligent, capable young man he was now, the result of nothing but _this_ world….

Zeff had been there, not them. And perhaps his protectiveness was a little possessive now too, particularly when Sanji's eyebrow twitched, his jaw clenching as if not entirely convinced by his order, by the fact that he wanted nothing more than to _protect_ the boy.

It wasn't as if he hadn't _wanted_ to tell him…..but then Sanji had met Ace….and Ace had been in the Navy...and the risk was too great...

"I need to think," Sanji muttered, and turned on his heel quickly, fumbling at the front door for the knob before he pulled it open and hurried out in a rush, leaving Zeff standing there in his wake.

Through the slats of the window shades, he saw the boy hurrying quickly towards the research building, and Zeff found himself slowly crossing back to his chair, where he lowered himself down and sat for a long time, staring blankly at the muted TV screen, now playing a cheesy commercial of a family finding something far too amusing as they ate out at a restaurant.

He sat there long enough that, eventually, the sun outside dipped even lower, and the room was more illuminated by the TV than it was the ambient light.

Out of the corner of his eye, he heard the faint sound of a car starting from the small parking area behind the lab, saw the beam of headlights flash bright against the building's white exterior, the palm trees casting crooked shadows as they waved.

The headlights swung away, and there was a glimpse of red taillights before the sound of the tires faded, leaving Zeff in darkness once more.

* * *

Zoro definitely wasn't _giddy_. He didn't _get_ giddy, not even after the occurrence of something immensely good. And yeah, Sanji doing the kiss thing with him had been pretty fucking great.

But he wasn't _giddy_ , dammit. His smile was just persistent, and so was the stupid desire to twirl in a circle as he swam and gleefully punch something.

Fuck.

Merpeople didn't do the whole romance thing like humans. At least not sharks. It was beyond him, or so he'd thought until Sanji's touches had started to feel like a warm current against his skin, and his smile became a beacon of light in a dark trench.

And that didn't even cover how he felt when they argued, how much Sanji's pissed-off tone, even if he couldn't understand half his words, riled him, fueled a pleasant boiling point in his gut that he hadn't really known was there. Not in him. In others, sure, but he'd always been….well, he'd been solitary. And he hadn't minded that in the slightest.

But in the short time he'd known him, Zoro had felt drawn to Sanji, a _human,_ in a way he'd never felt with anyone else. It was a desire to be near him, and a desire to protect him.

That Sanji was also male played no factor; that wasn't the surprising thing.

It was the fact that he felt _anything_ at all.

It was the fact that Sanji's lips on his, his taste, his scent, everything, had awakened affections long dormant, even seemingly nonexistent within him.

It was the fact that he now felt downright giddy after-

Fuck. Back to that again….

But he couldn't help it when all he could think about was the feel of Sanji's warm breath over his lips, how reassuring it had felt to pull him back into the water, feel him change back into his true form.

He'd known from the start that there was something different about the blond, since he'd first awoken to see the man from inside that strange tank at B.A.R.A.T.I.E., dead asleep in his chair...

He just never could have anticipated _how_ different.

Tomorrow. Tomorrow he'd be back, and honestly, it was probably for the best. Sanji needed time to process everything he'd been told, talk to Dr. Red. But that left _Zoro_ very unoccupied, with no choice but to head back to Noah, maybe get the Queen's thoughts on it all. He'd at least survived what might have been her impending wrath.

Still, he chalked it up to his dumb giddiness (which, yes, he reluctantly accepted) that it took several hours longer than anticipated to make his way back to the sunken ship.

It wasn't like he minded. It let him get some evening hunting in, eat something when he hadn't all afternoon, and it got his blood pumping for a different reason, ultimately calming the bubbly feeling in his chest by the time the lights of Noah finally became visible in the darkening waters.

He'd go to his quarters and sleep for a while, a small secluded room on a lower deck, that the Queen had told him was a room for third class passengers, whatever that meant. It was quiet and its size didn't matter. He had hardly any possessions.

His relaxation didn't come, however, because the moment he reached the deck of the ship, he was nearly tackled by a body colliding with his in a stream of bubbles, hands squeezing his shoulders.

" _Zoro-bro!_ " Yosaku exclaimed, his eyes wide and shining in the light from the main entrance to the grand hall.

Zoro merely grunted, passively let the force of the collision move him a couple feet in the water.

" _Yeah?"_ he muttered, balancing Yosaku's frantic energy with his own calm reply.

He noticed his friend hadn't let go of him just yet, his gaze flicking over Zoro's shoulder, to the space beyond him as if someone else should be there.

" _We heard about-"_ he started to say, then shook his head, bringing his eyes back to Zoro's. " _Where's Sanji?"_

Zoro tried not to let the mention of Sanji's name knock him right back into that whirlwind of _feelings_ again, merely shrugged and replied, _"Back at B.A.R.A.T.I.E. Why?"_

Yosaku frowned, strangely, but he eventually nodded. Zoro didn't like the way he closed his eyes for a brief moment, as if preparing himself for what he had to say next. It certainly heightened Zoro's attention at the very least.

" _We…_ " Yosaku began slowly. " _We might have to station fighters around our waters."_

Instantly, Zoro's eyes sharpened, lips pulling back in an automatic grimace of warning. It had been a while, _years_ since they'd last needed an active defense force, and the call for one meant there was an immediate threat.

A sickening pang in his chest that maybe this had to do with _Sanji_ somehow, but - that made no sense. The M.A.R.I.N.E.S. didn't know he'd come. He trusted no one on land had informed them.

" _Why?"_ he growled out with increasing anger, Yosaku immediately releasing his grip on his shoulders to hold hands up placatingly.

When he didn't answer immediately, Zoro drove himself closer, into his friend's personal space, sharp teeth on display.

" _Why, Yosaku,"_ he demanded, the other merman's shoulders slumping as he averted his gaze down to the deck.

" _Just….go ask the Queen…"_ Yosaku said quietly, his eyes lifting to the black beaded necklace floating gently around Zoro's neck.

He didn't have to tell him twice. He'd barely gotten the words out before Zoro turned tail and darted for the doors without so much as waiting.

* * *

Zoro's heart thumped fast in his chest as he made his way through the great hall, down the staircase to the lower level where he was sure the Queen would be, particularly at this time in the evening. She was always in her study, doing some reading or whatever the fuck she did in that side room she never let anyone enter.

He swam fast, the halls thankfully staying put where they were supposed to be, enough that he managed to get to Reiju's study in under a minute.

Zoro had no idea what she would be doing inside the room, but he heard voices as he approached the door, and, with the thought in his mind that danger could be coming, he burst right through without even knocking.

" _What the hell's going on? Yosaku just said-"_ he hissed, but stopped short when he found, inside the warmly-lit room, floating over the couch and chairs, the Queen and four merpeople he didn't recognize.

All of them turned to look at him, three mermen and a mermaid, and his heart stuttered in his chest for reasons he wasn't sure of yet.

Until he slowly began to make sense of the scene before him.

The mermen were a similar-looking trio, all with brightly-saturated heads of hair….and eyebrows that swirled in a very familiar fashion….their long ribbon-like tail fins twirling lightly in the water.

Two of them, one with green hair, more yellow than Zoro's own, and another with an electric blue mane flopped over one eye, quirked brows and looked to be barely restraining a pair of disdainful scowls at the interruption.

But they didn't matter. Because Zoro's gaze had fallen on the mermaid, who was looking over her shoulder at him, her dark blue-black hair floating around her face like a cloud of ink, seeping towards him to rewrite his memories.

Her tail curled over the edge of her chair beneath her, gray with darker ring shapes peppered near her fins, white T-shirt clinging, ghost-like in its translucency, to her pale skin.

And her eyes widened when they met his, filling with a sudden shimmer of emotion, her jaw dropping.

Zoro could feel his chest tightening because while he didn't recognize this woman….his mind saw beyond how she looked now. Time rewound itself until the mermaid seated before him was but a young girl, screaming for him on the deck of a M.A.R.I.N.E.S. ship, just before she was lost forever….

Or so he'd thought.

" _Kuina…"_ he shuddered out, his entire body beginning to tremble powerfully.

Her lips moved, voice barely audible.

" _Zoro…"_

* * *

Sanji was zooming a good twenty miles over the speed limit in his little blue sedan, but it didn't matter because the roads were clear and it was helping to channel his pent-up emotion.

The fading sunlight flickered through the silhouettes of palm trees along the road, the last of the glittery orange light sprinkled over the ocean's surface beyond.

His window was open, letting the warm air whip through his hair, send his joke gift from Ace dancing, the little hula girl, hanging from a thick string of wooden beads looped over his rearview mirror.

On the passenger seat beside him sat his laptop, hastily thrown there atop the black leather, and he knew the collar of his shirt was sticking up on one side, having pulled that on just as quickly, but he didn't care.

 _Ace_ wouldn't care, even though he'd forgotten his phone and couldn't even text him to see if he was free. It was a weekday night, but he should've been off-duty by now. The only pain in the ass might be getting into the naval base, depending on who was working the gate...

Still, he'd worry about that in fifteen minutes.

Sanji gripped the steering wheel hard and floored it along the coast, his car's small engine straining.

* * *

Indeed, his time estimation was accurate, as roughly fifteen minutes later, Sanji turned off the main road, into a small roundabout circling a large sign marking the East Blue Naval Base, now spotlit by a series of lights nestled in the neatly trimmed grass surrounding it.

The roundabout was empty, no line of cars backed up at the gate as there sometimes was, and there was a single light on at the gatehouse bisecting the road ahead.

Sanji took the brief moment before he reached it to straighten out his shirt, make sure he had his B.A.R.A.T.I.E. ID ready to show. It wasn't always enough to get him in without questioning, but he was quite good at telling a smooth white lie when he needed to. He'd been over here enough over the years that most every gatekeeper knew him and his father anyhow.

Window still down, he slowly rolled up to the large metal gate, a pair of officers standing sentinel on either side, weapons clearly in view.

It was getting too dark to recognize them, but he knew they wouldn't address him anyway. Once stationed, they took their job incredibly seriously, hardly ever moving out of position.

Besides, he was more concerned with just who would pop out of the gatehouse.

Thankfully, it was a familiar face, with eyes that were deepset and kind beneath the brim of his blue camouflage cap, his matching jacket and pants tucked neatly into high black boots.

Beneath the stitching of the Navy's insignia on the left side of his chest, the name 'Marco' sat rigidly in a yellow sans serif.

Despite how he'd felt driving over here, Sanji resisted the urge to smirk, especially when Marco exited the gatehouse and approached his car, barely suppressing one of his own, though he stood militantly, hands clasped behind his back.

"Mr. Red," he said, in his professional voice, most likely for the benefit of the grunts within earshot at the gate, a voice that was quite different from how Sanji knew him to sound when he was barking complaints about Ace, or drunk for that matter. "May I ask your business in the base?"

Marco knew full well. Maybe Sanji's dad came relatively frequently, to discuss environmental concerns, but when Sanji wasn't with him, he came for one reason, and one reason alone. And that was to see Ace.

"Got some new reports about the reef to drop off-"

"Ah, yes, to Captain Portgas, right?" Marco cut in, and Sanji nodded, grateful for Marco's understanding, especially now when all he wanted to do was see his friend. "Please wait here. I'll call him."

He turned on his heel then and disappeared back into the gatehouse, and through the door's window, Sanji saw him pick up a small radio on the desk along the wall, punching a few buttons before bringing the device up to his mouth.

He said a few inaudible words into it, waited a few seconds, and then his face promptly burst into flame, his soldier's demeanor dropping like a hat as he brought a hand up to his head, fingers sneaking beneath his cap to rake in a tuft of blond hair.

Marco growled something back, and then his hand was covering his entire face, as if he wanted to die right there on the spot. A brief look of exasperation, then he pointedly turned off the radio, straightened his cap, and came back outside to Sanji's car, a hint of fluster still evident in the way he cleared his throat.

"I'll escort you," he said, then turned to one of the men standing near the gate. "Palms. Take over the house until I'm back. Shouldn't be long."

One of the men, a young-looking guy with black curls visible beneath his cap, obediently moved away from the fence to head into the gatehouse.

With that, Marco shot Sanji a look, silently imploring he _do something_ about Ace, a look Sanji knew well, and he watched as Marco moved to stalk ahead of his car, around the corner of the building to where a large Navy jeep was parked. He climbed in, gave a short gesture with his hand out the window, then started up the car to pull out ahead of Sanji, Palms sticking his head out of the window of the gatehouse as he opened the gate from inside.

In front of both cars, the tall metal fence gave a screech, then slowly began to slide right, opening the way before them to another stretch of road, lined by palm trees, that came to an intersection where the visitors center of the base was settled.

Marco flipped on his headlights and started off down the road slowly, Sanji following him.

* * *

It wasn't long before they reached the residential area, the short drive through the self-contained base reminding Sanji of a high-security college campus in a way.

The base wasn't huge by any means, but the residential block was still pretty substantial, a large, unadorned rectangle of a building that rose up five stories on the outskirts of the base and stretched out over the length of a city block.

Marco pulled up to the sidewalk curb outside the parking lot to the building, full of personal cars, one of which Sanji recognized as Ace's flaming orange jeep, its doors already removed in anticipation for summer.

Sanji stopped before turning into the parking lot when he saw Marco switch on his hazards and hop out of the jeep, jogging over to Sanji's passenger side window.

He rolled it down, and Marco stuck his head in, resting his forearm on the low roof of the car.

"Hey, is everything okay?" he asked, far more relaxed now that it was just the two of them. "Ace said you didn't text him."

Sanji sighed, knowing his unannounced arrival at the base itself was probably strange, particularly when he usually _did_ text so Ace could have an excuse ready.

Still, as great as Marco was, he didn't quite feel comfortable telling him the full details, certainly not about the merfolk….

So he waved it off, forcing a tiny smile.

"Yeah, I just….well, to be honest, me an' my old man got in a fight. Kinda wanted to - I dunno, Ace gets it, so-"

"Gotcha," Marco cut in with a sympathetic upturn of lips. "Hope everything works out, man."

"It will," Sanji assured. "Just had to get away for a bit."

Marco nodded, then patted the roof of his car and stepped back.

"Well, I'll leave you here then. I don't wanna cut you short, but try to head out by ten?" he advised. "That's when my shift ends, and I dunno how chill Jozu's gonna be."

"Yeah, don't worry," Sanji replied. "Thanks, Marco. Oh, and don't let Ace coerce you into anything you're not comfortable with."

"Any ti-" Marco started to say before his face caught fire again and he gave a small growl under his breath.

"Yeah, yeah," he muttered, gave a tiny salute, and moved back to his own car.

Sanji watched him go for a second, smile falling off his face as soon as he was out of sight.

He gave a sigh and finally turned into the parking lot.

By the time Sanji stood outside Ace's apartment door, waiting for him to answer, with his laptop tucked under his arm, his heart was back to pounding, and that burning feeling was back in his eyes.

He rocked anxiously on the balls of his feet, the sound of crickets and frogs loud in the night, the hallway of Ace's third floor apartment open to the outside air.

Finally, there was the click of a lock, and the door swung wide to reveal Ace, shirtless, clad only in a pair of ridiculously long socks and a pair of gym shorts with his name printed down the side in varsity font.

His smile was bright though when he laid eyes upon the blond.

"Hey, you surprised me! You didn't tex-"

"Are you here alone?" Sanji blurted out, despite knowing he probably was, considering Marco was working, and he was currently the only one Ace was trying to hook.

Ace looked a little confused by the question, tilting his head and opening his mouth for a long moment before finally replying, "Huh? Oh, yeah. Sucks for me. Marco's gotta be up at oh-four-hundred to get a hurricane simulation going for the new kids. I told him we could squeeze in a quick one, but he's still playin' hard to get. He'll warm up tho- oh, alright, cool, come on in."

Sanji had interrupted his jabbering to push past into Ace's kitchen, through the small space into his sparsely decorated living area, walls empty save for a silly band poster over the TV that currently played a noisy wrestling match.

Ace was quiet as he studied Sanji's back, watched him move jerkily to the couch, where he immediately plopped his laptop into his lap and turned it on with several impatient jabs to the power button.

His fingers tapped restlessly against the edge of the keyboard, and his breathing was off, coming in short huffs.

He knew Sanji, and he hadn't seen him like this in a long time.

"Sanj…" he murmured quietly, letting the door close behind him as he crossed over to the living room too, grabbing the TV remote and flipping it off so he could give the blond his full attention. "Is everything okay?"

Sanji didn't look up, just typed his laptop password quickly and opened up his user folders, clicking through almost frantically.

Finally, when he had what looked to be a folder of pictures open on his desktop, he let out a forceful breath and turned to look up at Ace.

"No," he answered truthfully. "It's really not."

Ace stared at him for a long moment, worry spiking through his chest, but he kept calm, replying, "I….alright…" before slowly walking across the room to sit down beside Sanji carefully.

Sanji closed his eyes briefly, his hand lifting to tilt down his laptop screen a bit.

If he didn't tell Ace now, he never would. And he trusted Ace. He knew he would take this information, and its confidentiality, seriously.

He turned to the freckled man with conviction blazing.

"Ace, what would you do if I told you merpeople were real," he said bluntly.

Ace tried not to laugh, despite how unexpected Sanji's question was. After all, the look on Sanji's face was dead serious.

The most he allowed was a tiny smirk.

"I'd - ask you if they were hot-" he answered truthfully, wiggling eyebrows to gauge Sanji's reaction.

But when all he received was an unamused _look_ , he held up hands in surrender.

"What...?" he asked slowly instead. "Are you fucking with me….?"

Sanji didn't break character though, just stared, his hand still protectively poised over that laptop.

That was absolutely Sanji's cut-the-bullshit look. It was a look known to shut up even the most worthy of adversaries, including Luffy, a near unstoppable force when it came to wreaking havoc.

"You're….not fucking with me…" Ace muttered, resigned, with growing confusion, particularly when Sanji merely swiveled and pushed open his laptop again, pulling up the folder of photos once more, the thumbnails still too small to give anything away.

"Remember that guy the other night?" Sanji asked. "Our new intern? Zoro?"

Holy shit, how could Ace forget? The guy had shown up, and the tension between him and Sanji had been thick enough to cut. And yeah, he'd turned out to be cool too, if quiet, though Ace blamed that on whatever language barrier separated them.

"Oh, yeah, the gorgeous foreign dude!" Ace exclaimed with a nod. "Whatever happened with-?"

Swiftly, Sanji selected all the photos in the folder, hit the fullscreen shortcut on his keyboard, then dropped his computer into Ace's lap without further word.

Ace sat back a little, startled, but turned his attention to the first photo on the screen, which, at a glance he'd assumed to be nothing but a fish.

But upon second glance...

His eyes widened entirely.

"Wait…." he said slowly. "What the _fuck?"_

* * *

 _ **O.H.A.R.A. - West Blue - Hours earlier**_

* * *

Robin sat, posed casually on a deck chair, one leg crossed over the other as she sipped at her small cup of coffee. She remained composed, and yet her mind was working a thousand miles a minute, processing all the information Smoker and his colleague, Tashigi had detailed, along with the information the two helpful insiders, Coby and Helmeppo, had disclosed about the M.A.R.I.N.E.S. and their mer-inhabitants.

The icy light from the grotto shimmered over her guests, Franky beside her, leaning heavily onto his knees, Chopper and Brook hovering nervously in the background. Even Nami had closed up the main lobby and joined them, seated on the stone stairs to the library with her own steaming mug of coffee gripped between both hands.

So the M.A.R.I.N.E.S. had kept prisoners. All these years, since Zoro's rescue, since _Sanji_ had been a baby, the M.A.R.I.N.E.S. had held merpeople, and Robin wasn't sure if this disgusted her more than her previous belief in their deaths.

The M.A.R.I.N.E.S. was craftier than she'd thought. Craftier and far more despicable.

And rather surprisingly, it seemed Smoker was of the same school of thought as she, despite working under them for as many years as he had.

But she supposed learning the same things she just had was enough to push anyone decent over the edge, even the most loyal of colleagues.

There was one thing for certain, however.

"We must act," she said decisively. "We must act immediately before the M.A.R.I.N.E.S. can recapture them."

She was worried. If the M.A.R.I.N.E.S. had already mobilized in search of the escaped merpeople….

Well, she didn't want to think about what that would mean for the colony. For any of their mer-friends….or now for Sanji, knowing Zoro's plan to show him the truth.

"I just….can't believe Dr. Red wasn't gonna help out," Franky said beside her, running a large hand back over his head, gripping the neck of his cola bottle loosely with the other. "I mean, doesn't he got Sanji-bro to worry about?"

"My guess, at the moment," Robin mused. "Is that he worries more for Sanji's secret resurfacing. However, I have a feeling, in light of recent events, said secret will be coming to light whether he likes it or not. If it hasn't already."

Franky shot his girlfriend a curious look, quirking a brow. She glanced over at him and subtly rubbed at her wrist.

It took him a minute, eyes dropping to her slender fingers, but they soon widened in recognition.

"What can you offer in the way of protection, Dr. Nico?" Smoker interrupted, his broad form clearly too big for the beach chair on which he sat, his own empty fingers tapping agitatedly on the arm rest, the need for a cigar growing the longer he sat. "Because whether the old man's willing to help or not, we've still got a problem. Not only did the four of them escape, but the mermaid took a bracelet, as far as we know."

This snapped both Franky and Robin's attention back to the other man, Chopper and Brook sharing a glance behind them.

"You mean to say the M.A.R.I.N.E.S. had possession of a bracelet?" Robin asked, and this time, it was Tashigi who nodded, anxiety clear in the uncomfortably rigid way she perched on her chair, held her tea cup with both hands.

"Yes," she confirmed. "I'm not sure how she got it, but she used it to help her and the princes escape. She managed to tie me in a closet to ensure I didn't stop her."

A nervous chuckle, Coby touching a hand down on her shoulder to pat her comfortingly.

"It's true," the younger man said, adjusting his glasses atop his head. "It's possible she took advantage of Fullbody somehow. He's got a bit of a weakness when it comes to women…."

"Not to mention he was found unconscious near the tanks…" Helmeppo added under his breath.

"It doesn't matter," Smoker interrupted with growing impatience. "Fact is, she has it, and they're gonna stop at nothing to get it back. Now what are our options here?"

It was Franky who answered, having laced fingers with Robin, giving her hand a reassuring squeeze.

"We got the Sunny, the Merry, and the Mini Merry here," he explained, naming off their three main research vessels. "Me an' Robin can take Sunny out to block 'em. Try an' negotiate. Or at least stall 'em. Brook here can head out to East Blue, I'm thinkin'. Make sure everyone's warned, though they probably know already. But they gotta get to safer water."

That left one remaining cause for concern, clear in all of their minds, including Nami's, the redhead pushing up from the stairs and stepping closer to the group.

"Do you think it's time the Navy found out?" she asked, placing a hand on her hip and looking expectantly to Robin.

The Navy had no idea, after all, about the existence of the merfolk. For fear of government involvement, the conservation groups had worked hard to keep the secret, and while the M.A.R.I.N.E.S. had also kept up their end of the secrecy pact….there was no telling if they would now. Now that they no longer possessed what they wanted to protect…

"And what makes you think it's a good idea to involve them?" Smoker grumbled, unconvinced. "Do you want Navy ships squandering their whole colony?"

"Relax, old man. Only the West Blue base," Nami assured, reaching out boldly to slap a hand at Smoker's back. "It just so happens I trust the Vice Admiral more than anyone~"

Robin sighed, shoulders slumping a bit as she smiled gratefully at her younger friend.

"I suppose you have kept the secret from your mother for far too long, haven't you," she admitted.

* * *

 _ **East Blue Naval Base**_

* * *

"This isn't Photoshopped."

"No."

"Do you _promise_ you're not shitting me?"

"Ace, look at the fucking database! Look at all the shit there. I swear on the geezer's life! I swear on your life, on - on Luffy's life, Sabo's - _my_ life! Everyone's fucking life! I'm fucking _telling_ you it's real, and I could _never_ make up what I saw today!"

Ace lifted his eyes from the screen, full of unbelievable images and information regarding _merpeople_ of all things, to meet Sanji's desperate gaze, the blond's hand, which gripped his wrist, practically trembling.

He could feel Sanji's energy and emotion, hear it in his voice, see it in his eyes when he'd detailed what had happened that day, how…..how he'd fucking _transformed_ and learned he was born to _merfolk_ that apparently lived not an hour away in the middle of the ocean and-

The more Ace tried to wrap his mind around it, the crazier it sounded, but Sanji was serious, that much was obvious, and….well, merpeople aside, he'd just learned a fuck lot about his birth family that had been _kept_ from him by his father.

That was reason enough to believe him, to support him, Ace knew.

So he shifted the laptop to the small coffee table in front of him, shoving aside some empty beer cans and turning himself to fully face the blond.

His hands rose to squeeze Sanji's biceps, and he made sure to look into Sanji's eyes as he said, "Okay, Sanj. I believe you."

Sanji blinked at him in shock for a moment, admittedly surprised because he expected to have to fight this longer than he had. He wouldn't necessarily categorize Ace as the most logical person he knew, but he was certainly more on the seeing-is-believing side of things.

And yet, his thumbs were rubbing gentle circles of reassurance into Sanji's skin, just as they used to when Sanji was unsure about very different things. He held onto him, and his lips turned up, a little crookedly, in that endearing way.

And the relief was so great, that relief of sharing his feelings, how he'd felt, knowing his dad had kept things from him all these years, regardless of his reasons….

Tears automatically welled in his eyes, enough that a flash of panic came over Ace's face, his hands immediately migrating to Sanji's cheeks, where the freckled man stroked, his body moving closer.

Sanji clenched his teeth, sniffed, then fell into Ace's chest, releasing his tears like a pathetic child.

But Ace didn't care. He simply brought strong arms around Sanji and held onto him protectively, murmuring soft words of comfort in his ear.

It took a while for Sanji to calm, and even when he did, he stayed close to Ace, letting the older man hold him, and taking comfort in the fact that they could still do this, that Ace meant enough to him that they could move on from their romantic past and support each other with a different kind of love.

He could tell Ace was still baffled from everything he'd learned, but he was pushing that aside in favor of comforting Sanji, listening to him as he helplessly murmured into Ace's shoulder, "He should've just told me…..I wouldn't have told anyone. He should have trusted me."

"I know, Sanji, I know," Ace replied quietly, pressing a kind kiss to blond hair before resting his cheek there. "But do you really think you woulda sat with that knowledge for this long and _not_ tried to go lookin' for 'em?"

Sanji made a miserable sound, because he knew the answer to that was a hard 'no', but he still didn't want to admit it. Not while he was still angry with his dad, and devastated about his family history…

Ace just chuckled, squeezed him a little tighter, then decided to distract him a bit with something else he was curious about.

"What about Zoro?" he asked, and he was pretty sure he felt Sanji's face heat against his bare skin, enough that the blond sat up, and yes, there was a blush there as he rubbed at his wet eyes and cheeks.

"What _about_ him?" Sanji shot back with an attempt at a scowl.

Ace merely raised an eyebrow and shot Sanji a knowing look over a growing smirk.

Sanji glared at him for a second….but then gave in rather quickly with a roll of eyes.

"Of course we made out-"

Just in time for Ace to burst out cackling, holding a hand to his stomach as he fell back to the couch.

"Ahhh," he cried after a minute, now having to wipe tears from _his_ eyes. "I love it. It's so like you to fall for a _merman."_

"Shut up," Sanji shot back half-heartedly, finding he had to resist the urge to smirk at Ace's reaction. "I _am_ a merman, y'know. There's no weird interspecies thing…" Thank _fuck._

"No, it's just a very _Sanji_ thing~" Ace said, amidst more snickers. As if it made any sense to anyone but him.

This earned him another roll of eyes from the blond, though it didn't last long before he was back to looking uncertain. Hands wrung awkwardly in his lap, prompting Ace to take hold of them gently.

There was more Sanji wanted to say, and Ace could sense that, so he waited patiently, a soft smile on his face, his mind drifting to how Sanji might have looked as a merman. He hoped he'd get to see it one day…

But...would he? After what Sanji had told him, about the M.A.R.I.N.E.S.' repeated insistence on capturing merpeople, about how they'd _died_ ….

Even if Sanji was safe right now, because of his dad, would he always be safe? This sent a spike of worry through Ace's heart, and he struggled to push it down, to keep a frown from coming to his face.

He waited until the blond sighed, then met his gaze again slowly.

"Ace, you can't tell anyone," Sanji pleaded quietly. "Please. Not even your brothers. Not until….not until I'm _sure_ all of this is going to be okay…."

After all, his dad had said the Navy's ignorance was actually keeping him safe. He trusted Ace with his life, but he still felt the need to say it, given what had been mulling around in his mind for the past few days.

And it was the way Sanji said it, with conviction and an air of finality that only served to enhance Ace's worry, the freckled man's eyebrows lowering.

"What do you mean…?" he asked cautiously. Until it dawned on him with a skip of his heart. "Wait, you're not thinking of talking to the _M.A.R.I.N.E.S._ about all this, are you?"

Sanji didn't deny it, merely leveled Ace with that serious gaze.

"I don't have a choice," he said. "Now that I know. No one else has confronted them. Not for - a long time. And I'm not afraid of them. They're only humans."

Ace balked though, his heart picking up speed and his grip on Sanji's hands tightening inadvertently.

"But - But, Sanji, you said people have _died_ ," he reminded, though Sanji responded quickly.

"Who else is gonna talk to them!" he insisted. "After what they did to my family, I can't just - sit around and do nothing!" The blond let out a breath and shook his head, lowering his voice then for a cheap tactic. "Are you saying you wouldn't do crazy shit for Sabo and Luffy?"

Ace already had his mouth open for another retort, but he quickly shut it, narrowing eyes at Sanji and muttering, "That's not fucking fair."

Sanji shrugged and held hands up, a gesture that illustrated he was completely out of options, and dammit, that was how it felt. It wasn't just his family and his past. When he thought back to the look on Zoro's face, that distant pain and trauma that still haunted him when he mentioned his lost friend, Kuina….

No. This shit needed to be atoned for.

"I have no choice," he repeated resolutely, prompting Ace to let out a heavy sigh, lifting one hand to pinch at the bridge of his nose for a long moment.

He composed himself, but then reached right back to take Sanji's hands again to drive home his next words.

"Let me help you," he said, despite not knowing how he would, but the blond instantly shook his head.

"No, Ace, I've gotta do this alone-"

Ace let out a growl of frustration, throwing his head back towards the ceiling.

"Then why tell me all this?"

"Because, I just-" A forceful exhale, that was a little guilty, before he finished, "Needed to get it off my chest…..and come on, Ace, you're my best friend. How could I _not?"_

As if that would appease him, and Sanji knew he was still irritated by the way he focused his gaze at the blank TV screen, clenched his jaw.

Eventually though, he flicked eyes back to Sanji, stared at him for a long minute, then finally brought his head around to look at him properly again.

"Just….promise me you won't get hurt," Ace insisted, hands squeezing Sanji's almost desperately.

Sanji sighed, lips turning up a little.

"As if I would," he muttered. "That's the farthest from my intentions-"

" _Promise me,"_ Ace implored, leaning in closer and ducking his head to look Sanji directly in the eye.

"Okay, I promise," he assured, squeezing Ace's hands back.

Ace glared at him…...but eventually settled back again.

"And you also gotta promise me I get to see you transform," Ace demanded next. "I believe you, but I wanna see this shit in action. You do realize you're living a movie right now?"

Sanji couldn't help a grin.

"A good movie, I hope."

"Oh yeah. A musical. With tie-in toys at all the fast food joints. Because we know how much you love fast food~"

Sanji pulled his knee up and nailed Ace in the chest with his foot.

And though the two of them might have diverged into their normal teasing banter for another half hour, there was still a sinking worry in Ace's gut by the time he stood in the doorway to wave goodbye to Sanji.

If all of this truly was real, then Sanji could be in very big danger, especially after essentially spilling the secret to the Navy….

Sanji trusted him not to tell anyone. And Ace desperately wanted to uphold that. He didn't _want_ to break Sanji's trust.

But he also didn't want any harm to come to the blond, and considering there had been _deaths_ related to all of this….that fear was enough to have him seriously questioning himself.

Because he had people he trusted too. He knew the Navy was full of good people who would surely want to stop the unethical practices of the M.A.R.I.N.E.S. And they had the means to _help_ ….particularly his commander….

The question was, would Sanji forgive him, even if it helped matters in the end...?

Sanji descended the stairs at the end of the hallway with one last wave, leaving Ace alone, a hip propped against the door frame.

He stood there until he heard the sound of Sanji's car starting down in the parking lot, driving off down the road.

Ace ran a hand down his face and turned back into his apartment, the image of Sanji's pained tears persisting in his mind longer than even the unbelievable images of Zoro and his magnificent shark tail.

Fuck.

He needed to think….

* * *

 _ **Noah - East Blue**_

* * *

Zoro watched as Johnny and Yosaku led the three princes, Ichiji, Niji, and Yonji, off down the hallway to find spare rooms for them to sleep in.

He'd hardly paid attention through the whole awkward meeting, one reason being it had taken place entirely in human language. It seemed the princes had never learned their own mother tongue.

Zoro had zoned out, only understanding about half of what was said anyway, and besides, he could already tell. The brothers were nothing like Sanji. They looked like him, their facial features incredibly similar, but they acted cold and distant. They'd detailed their escape from the M.A.R.I.N.E.S. very clinically, and they were hardly even reacting to Reiju like Sanji had.

They explained their years at M.A.R.I.N.E.S. HQ, years that must have been lonely and dark. They showed none of the empathy in their eyes, the emotion and kindness that Sanji showed, nor did they seem to sense the weariness in their sister, the Queen clearly overwhelmed and confused by the shocking appearance of her other siblings, assumed dead.

The connection between them didn't click nearly as well as it had with her and Sanji. Zoro could hear it in Reiju's voice, see it when she lifted eyes to him with an exhausted stare.

It only justified for Zoro that there was indeed something special about Sanji, and Zoro had to wonder how much of that was chalked up to the brothers' different life experiences. Probably a lot….

Perhaps he should have sympathized, knowing what the three had been through, where they'd been all these years.

But he found he could hardly focus on anything but one thing as he hovered there, still close to the door, his heart beating fast in his chest. And that thing was Kuina, who hadn't said a word apart from his name when he'd come in, though she seemed acutely aware of his presence.

She'd looked steadily away from him while the brothers talked, but her posture was too rigid, and her eyes clearly wanted to flick his way.

Thus, the meeting had passed, with promises to speak more in the morning when the four of them were rested from their journey.

The brothers had left, and Reiju had risen as well, turned to Kuina in the doorway, her gaze softening a bit. After all, she and Kuina had spent much time together growing up, and Reiju lifted hands to squeeze the other mermaid's forearms.

It was clear neither knew what to say, how to react to finally seeing each other again, as adults, after fourteen years, during which Kuina had been believed to be _dead._

Still, in a rare moment of genuine emotion, Reiju smiled softly and murmured, in their own language, " _I'm - I'm so glad you're alright,"_ letting out a slightly embarrassed chuckle at her own inability to say something more substantial.

But while Kuina looked similarly emotional, there was also a bewilderment there, particularly when she replied sheepishly, "I-I'm sorry, but - I don't - remember a lot of our language…"

She trailed off, and Zoro could do nothing but stare as sadness flashed in Reiju's eyes, though she quickly masked it with a smile and reassurances in human language before calmly ushering her from the study.

A look she shot over her shoulder though, at Zoro, still frozen in place, and she jerked her head towards the hallway imploringly.

He followed, almost in a trance, all the way to the end of the lower level hall, to Kuina's old room, a place none of them had visited much since she was taken.

The wooden door was difficult to open, from years of disuse, but it had opened onto the same scene all three of them remembered, a square room, dark, but tinted blue by the large porthole in the wall. A small, slightly-tattered human bed rested against the wall, hardly there for anything more than aesthetics at this point, considering barnacles had begun their slow takeover of its tarnished brass frame.

There was almost nothing else in the room, just a bedside table and an old wardrobe against the wall, its doors unhinged and waving slightly like rudders in the slow current.

Kuina had been like Zoro, not one for having a lot of possessions.

But there was something she and Zoro both recognized instantly, the two of them in similar frozen states as their eyes fell upon the shiny white-hilted human sword they'd found, attached, on some kind of decorative plate, to the wall of Noah's sunken library.

They hadn't known what it was for, only that it was a weapon, but it had come to mean something to both of them, a symbol of strength, and maybe a bit of challenge, that one day they'd be able to swing it around easily, maybe even with one hand….

Zoro hadn't even noticed Reiju murmuring something else to the other mermaid, Kuina nodding and attempting a smile before moving slightly forward into the room.

What he did notice was Reiju turning away, giving him a push towards the door before she swam off towards her study once more.

What he did notice was that he and Kuina were suddenly alone, and though her back was to him, he knew she was aware of this fact too.

Why was it so hard to initiate something? Why was he suddenly fucking mute and unable to say the things he _should_ have said to his friend. Things he _had_ said to her, if only in his own mind, believing her to be dead.

What the fuck did he even do?

Neither of them knew how long it took, but it was Kuina who turned around first, her eyes downcast, closing for a moment before she finally looked up to meet his gaze once more, with a gaze of her own that was so familiar and yet so distant, from another time.

She looked at him for a long moment, and he at her, taking in everything that had changed, how her features had lengthened, and there was a hardness there that was a little more ferocious than even the determination he remembered. Her jaw clenched though, just as it used to, whenever they fought, when he'd get a move over on her, and leave her to calculate just what she needed to do to tilt the match in her favor.

What he hadn't expected was for that jaw to quiver not soon after, just slightly, but it was enough to reveal the emotion threatening to break free, and it made his own heart clench, particularly when she stuttered quietly, "I-I thought you were dead….."

He didn't know how to respond, in his own language, let alone human language, his complete and utter shock over the situation rendering him useless and numb.

He opened his mouth, but nothing came out, save for a few stray bubbles.

She was approaching him slowly, almost cautiously, and she floated in front of him for a few moments before allowing, ever so slowly, a tiny upturn of lips.

"You still - emotions still break you, don't they," Kuina mumbled, giving a small chuckle, before her smile faded and she brought a hand up to rub at her cheek a little self-consciously.

"Fuck," she muttered. "Do you even understand what I'm saying…?"

"Yes," he blurted out, surprising even himself because he hadn't quite planned it. But he forced himself to continue, especially when an almost relieved look came over Kuina's face. "I….understand….. Not - all - but-"

And just like that, her eyes widened and she dove forward with a flick of her tail, threw arms around him and hugged him tight, the move enough of a shock that he floated back in the water a few feet with the momentum.

But she wasn't letting go, and though he couldn't recall a time they'd _ever_ done this before, it didn't matter. Because she was alive. She was _fucking_ alive, and maybe he shouldn't have ever doubted her.

His arms came up to hold her back, and when they did, she squeezed him closer, a noise stuck between a laugh and a sob stifled against his shoulder.

"Fuck, I missed you, Zoro," she murmured after a minute, and his shoulders slumped, his chest feeling a bit lighter.

"Missed - you too," he replied, closing his eyes.

* * *

 _ **B.A.R.A.T.I.E. - East Blue**_

* * *

It had been many years since Sanji had used active avoidance as a tactic to deal with conflict, and particularly with his dad. Normally, he was more than willing to have it out with the old man, even if things got heated, or even physical. It was straightforward; it felt good to get his feelings out that way, and it felt even better afterwards, the act itself a release of sorts.

But after his visit to Ace's, Sanji found himself glad to see the lights dimmed in the bungalow, his dad already in bed.

He wasn't sure he owed his dad an apology for what had gone down, and he wasn't expecting one from the old man, so what else was there to say? Life would go on, and if one thing was certain, he knew he wanted to see Zoro again, regardless of his dad's wishes.

So he'd stolen away to bed too, stayed in his room the next morning until he heard his father get up and leave. Only then had he crept out to get ready himself, feeling absolutely drained, but he needed to talk to Zoro, as much as he could with the idiot's lack of general understanding.

Ace had been right, the night before. He shouldn't go to the M.A.R.I.N.E.S. alone, he could admit that now, but like hell he was involving Ace in something that might put his job on the line. And if his dad wasn't going to help him, then maybe Zoro or his sister would want in.

Those two had been the most affected, Sanji knew. They'd lost loved ones, ones they could _remember_ , and as much as he didn't want them in danger either, right now, they were the only ones he felt comfortable even bringing the topic up to.

That was why, as the sun began to poke itself up over the ocean's horizon in the distance, a sliver of orange just beginning to spill over the water, Sanji sat at the edge of the dock behind the lab, already waiting for Zoro to show up.

They hadn't specified a time, not that he expected Zoro to even adhere to that anyhow. And he was prepared to wait there all day if he had to. Nothing his dad could say would stop him.

It seemed Zeff wasn't willing to confront him either because he'd merely disappeared into the lab building without so much as nagging Sanji about the work that needed to be done that day.

Sanji watched the sea, bare feet dangling into the lapping water below, still cool in temperature after bathing in moonlight all night.

He closed his eyes, and thought about Noah, thought about its time-forgotten halls, the underwater rays of light like apparitions, the ship caught between nature and civilization.

He thought about Reiju, how difficult it must have been for her, to see him there, after an entire lifetime apart, to hear his desire to help, decades too late.

And then he thought about Zoro, about those beads around his neck…..and yet, the dopey grin on his face after they'd kissed, how idiotically happy he'd looked from such a simple thing and-

Sanji opened his eyes after a while to find the sun hovering, a full circle, above the horizon line. And bobbing in the water before him was a familiar tuft of algae, shoulders rising out of the water too until Zoro properly floated there, looking up at him.

Sanji didn't react, despite his heart doing a flip in his chest, merely smirked ever so slightly and quirked a brow at the merman.

What should they do? He wanted desperately to touch him, but was everything still okay, even if it had ended well the previous evening?

He got his answer a second later when Zoro lifted himself a little more to circle arms around Sanji's waist, both as leverage to hold himself up and as a gentle embrace.

He stared up at Sanji, a question in his eyes too, hair slick and dripping, and Sanji could no longer help it.

The blond lifted a hand to brush it back over Zoro's hair, then leaned in, natural flexibility allowing him to reach Zoro's lips with his own in a tentative kiss that became more confident the second Zoro pressed back.

It was still real, all of this, legs automatically curling around Zoro's waist, ankles pressing against the small of his back, where tail began to morph to skin, to bring Zoro closer.

He was surprised by how gently Zoro responded to him, how he matched Sanji's slow rhythm and brushed fingers over his back, teasing them up underneath his shirt.

It was different from how fiercely he'd moved the day before, and there was no wickedly triumphant smirk when Sanji pulled back for air, just a soft sort of look that was very human, and even a little….unsure….if that was even a word he could use to associate with Zoro.

Zoro's eyes lingered on Sanji's lips for a long moment, but then he too moved, slipping back into the water and unclipping that incredible metal bracelet from where it still dangled safely around his necklace.

He held it up for Sanji silently, the blond staring at it for a few heartbeats before looking away to glance over his shoulder at the lab building behind him, its white facade still a light pink in the early morning light.

He turned back to Zoro defiantly, took the bracelet and pulled off his shirt before sliding into the water himself, unaware that his father had stepped away from the window in defeat as soon as he saw that blond head disappear below the dock.

* * *

Zoro's hands on Sanji's waist guided him below the surface, stayed there when human skin transformed to the soft saturated tissue of his shark tail, and as soon as he was able, he leaned in to press lips to Sanji's again, finding it made him feel far less confused, far less worried about everything that had conspired when he'd gone back to Noah.

Kuina was alive, and while this brought him an immense sense of relief, one he hadn't known he needed, it also twisted his gut in new ways, to think that all this time, she'd been held captive, that she couldn't even remember her own native language.

Kuina was so strong, but….seeing how Sanji's brothers had acted, the merman had to wonder just how much those years had affected his friend as well.

Perhaps he should have stayed at the ship that morning, to be there to help her adjust, but he'd found himself unable to sleep and made his way back to B.A.R.A.T.I.E. early, relying on memory and instincts to get him there, the water still dark in the hours before the sunrise.

And now, though Sanji's lips trailed over his jaw, his arms coming up to fold over his shoulders, he could feel a slip in the blond's confidence as well, as if something had happened to rock Sanji's sense of security too. Maybe something with his dad…?

"You're such an idiot…" Sanji murmured against his cheek, his nose brushing Zoro's a second later, and Zoro opened his eyes, not quite realizing he'd closed them.

"Why…?" he asked, transfixed, despite the insult, by the way the blond's hair curled around his head, soft and voluminous.

"I don't know," Sanji replied with a shrug and a quiet laugh, leaving Zoro to roll his eyes.

Still, he had other things on his mind, things that were far more consuming than Sanji's stupid jibes - namely, how he was going to go about telling him that his three brothers, who, not one day ago, he'd learned were _dead,_ were actually perfectly alive. And perfectly assholes, but that was another issue entirely.

His body seemed to move of its own accord, arms tightening around Sanji's waist and his chin finding the other merman's shoulder, nuzzling there as his mind raced. But instead of feeling Sanji relax, the blond tensed, and he felt hands jump to his hair, Sanji pushing him back slightly with a frantic look in his eye.

"What's wrong?" he demanded. "Something's wrong."

Zoro shook his head without saying anything, because that wasn't exactly the issue, something being _wrong_.

Sanji's fingers pressed against the side of his head, his thumbs stretching down to touch his face just beside his eyes.

"Zoro…" he pressed, and there was enough worry in his tone, that Zoro decided he may as well spit it out. He wasn't trying to hide it anyhow.

"I…" he started, brow furrowing as he worked to find the words in human language. "Last night….Kuina…..not dead."

His grammar was way off, unsure of how to say half of what he wanted, but Sanji seemed to get the message loud and clear, his eyes widening, hair floating up around him to almost enhance his surprise.

"What…?" he stuttered with disbelief. "How do you know?"

His face was so dumb-looking in his shock that Zoro actually chuckled slightly.

"She….came back….to Noah…" he explained, Sanji's eyes widening even more, his jaw dropping.

Sanji seemed to forget to keep his tail moving because he started to sink lower in the water, so Zoro went with him until they were near the bottom of the barnacle-encrusted dock supports, where seagrass waved and tiny minnows darted.

The blond seemed to remember himself finally, his hands sliding down to grip Zoro's shoulders supportively.

"Well - Zoro, that's amazing, I - where has she been? She's-" he stammered, lips still caught between a smile and an oval of astonishment. His fingers clenched a little tighter into Zoro's shoulders. "Holy shit. Did she escape the M.A.R.I.N.E.S.?"

Zoro nodded, watching him, watching his eyes behind which he could practically see Sanji's brain working a mile a minute. For once, his speech sounded just as broken as Zoro's often did.

"I-" Sanji replied. "Wow, I-"

He stopped himself though, finally slowing and meeting Zoro's gaze again with his own, and Zoro appreciated when Sanji took pause, lifted a hand to stroke at his face.

"Must be a shock," he murmured, a bit calmer, migrating his touch to the three golden earrings dangling on Zoro's left ear. "I'm happy though….that she's alright." His touch stilled briefly. "She...is okay, right?"

"Your brothers…" Zoro said instead, blurting out what needed to be said. It was probably easier that way, in the end.

He was pretty sure he felt Sanji's heart skip a beat against his chest.

"...My brothers…?" Sanji replied slowly, sounding unsure of whether to be hopeful or scared, so Zoro was quick to clarify.

"With her."

Now Zoro was _definitely_ sure of a few abnormal heartbeats.

Sanji's fingers curled behind Zoro's ear, shoulders slumping as if to let out a shuddery breath that didn't come, of course.

"They're alive too…?!" he asked, overwhelmed.

Again, Zoro simply nodded, and there was a slight pang in his own chest when Sanji's next inquiry was, "My mom…?"

Zoro shook his head, leaned in to brush his nose to Sanji's apologetically, bumping his forehead against the blond's a second later.

He held it there, through the soft noise of disbelief that left Sanji, his hands eventually sliding numbly into Zoro's hair once more, where fingers stroked absently through their shock. Sanji had only just learned about his brothers, but to have their plight reversed on him so quickly surely messed with his mind quite a bit.

He gave it a few minutes, waited until the blond settled arms around his shoulders again in a hug, propped his chin on his own forearm and seemed to relax, though he was still quiet.

"M.A.R.I.N.E.S. coming," Zoro finally added and he could tell by Sanji's subdued reaction that he'd already deduced that much.

"Then we protect them," Sanji muttered, his voice close to Zoro's ear. "We protect everyone."

Zoro had expected that reply as well, his arms automatically tightening protectively around Sanji's waist.

"You can't fight, Question…"

"So teach me," Sanji shot back, an edge back to his voice. "Come on, stupid. I haven't done shit for you my whole life. Let me help now."

His mind sounded made up, as if this was a conclusion he'd come to on his own. He'd said similar things before, but this time was different.

Did he have a plan? Zoro didn't know, but when he pulled back to see Sanji's blue eyes blazing, jaw stubbornly locked, he knew there was probably no hope arguing with the idiot.

Instead, he kissed him, because maybe there was something Sanji could do. It was what he'd thought about from the beginning, after all, that Sanji might actually have a shot at changing things. He just hadn't been expecting an event like this to trigger the M.A.R.I.N.E.S.' hostility.

Still, Sanji's lips kissing back with more of the fervor he'd felt the previous day, the firm conviction in the way his hands came to either side of his head again, pushed Zoro back if only to fix him with a fierce glare that Zoro recognized as a fighting one….

All of it worked to speed his own heart, remind him why he'd come back to meet Sanji so quickly, so he could feel this again, feel like things were going to start moving, that Kuina and the princes _would_ be safe, despite not knowing how. It was a surprising confidence that Sanji instilled in him automatically, and it was unlike any he'd felt before.

He allowed a smirk to come to his lips, one that Sanji echoed with a flash of sharp teeth.

"Let's go," Zoro said.

* * *

 _ **Open ocean - East Blue**_

* * *

The morning sun shimmered its way above the horizon line like lava bubbling over the surface, slowly creeping its way across the glassy water beneath.

Sakazuki stood in the control room of the ship, his glare boiling as he clenched the radio receiver tightly in his fist, the crackly voice from HQ coming through, a little fearfully, on the other end.

" _Sir? Are you there? Sir! What should we do?"_

But the man's mind was elsewhere, as he recalled the ferocious face of Dr. Red, many years ago now, standing firm and protective on the docks of B.A.R.A.T.I.E., through which a small baby, a scientific anomaly like his brothers, had just disappeared through the building's doors.

He was human, but there was no telling what lay in his DNA, perhaps the key to hybrid fusions, information that was just waiting to be discovered, information that could help the medical and scientific communities for generations to come. He'd assumed Dr. Red would understand and know that, despite his desire to protect the boy, this would be for the greater good, just as it would be to study the boy's mother and brothers.

Instead, a compromise had been made to leave the boy alone, a reluctant one on his part. But he was a man of his word, and he'd trusted Dr. Red was one too.

Clearly, that wasn't the case, because he still had a frantic voice trying to get through to him.

" _Sir, you know Whitebeard! He'll call back! He - He might even send a ship over, and - sir! Please copy!"_

Whitebeard. The Navy admiral, commander of the East Blue base, had somehow come to know the entirety of their experiments, rather suddenly, with details _no_ _one_ should be aware of, save for someone who'd known the secret of the merpeople for decades, someone who now stood to lose everything, as far as Sakazuki was concerned.

Because even if that bastard Zeff hadn't told him, even if it _had_ been the boy or anyone else….that meant the secret had been leaked. That meant the pact with Zeff was no longer valid.

And that meant they now had a target perhaps more important than his brothers and the mermaid combined.

 _"Sir, what should-!"_

"Ignore any calls," Sakazuki finally growled into the receiver. "Now, we find Sanji Red."


	10. Healing

"I took kickboxing, y'know! Just 'cause I don't know how to wave this tail around properly doesn't mean shit! Get your ass up on land and I'll kick it to West Blue and back."

Zoro grunted in response, understanding about three words of what Sanji had said. Honestly, at times like this, when he was simply screeching for no reason, tuning him out was better. Instead, he focused on the water ahead, the direction of the waving sea grass that tickled them as they swam, following the currents across the rock field back to Noah.

And people got on him for his sense of direction. Obviously, so long as the grass _was_ waving, that meant he was going the right way.

It seemed Sanji's sense of amazement of the undersea world had worn off a bit, as now, he appeared to be much more focused on Zoro.

That wasn't necessarily a bad thing though, because the brushing of fingers against his arm, and the way the blond insisted on maneuvering himself in front of him time and time again, to see his face….it felt good, even if it was a little strange, and definitely a behavior native to humans.

Kissing him was pretty damn incredible, but beyond that, all these weird little mannerisms and the constant need for physical contact that Sanji displayed was definitely new, and he wasn't entirely sure how Sanji expected him to react.

"You don't even know what kickboxing is, do you," Sanji complained, interrupting Zoro's thoughts, though there was a twinkling amusement on Sanji's face when he twirled himself and dove down gracefully to swim beneath Zoro, looking up at him with a smug crossing of his arms.

"What?" Zoro asked, blinking down at him in confusion.

"Nevermind," Sanji scoffed with a roll of eyes, and he brought fists up to punch teasingly at Zoro's chest, still careful to avoid that healing scar, even if it was nearly faded now, several days after the injury. "Don't merpeople have sports?"

That word sparked recognition over Zoro's features because he remembered Robin and Franky showing him weird shows on TV, of humans running around, chasing balls, hitting them with shit, sometimes even swimming. The swimming was particularly ridiculous, watching them flail their arms about, splashing like seagulls in a tiny pool, moving at a sea turtle's pace.

That was "sports," and merpeople most certainly did not have them.

"No," he answered, with an air of relief to his voice, considering how foolish it made the humans look.

Sanji's face screwed into a pout for a moment.

"Well, that's boring," he replied, then flipped himself over Zoro so he could hitch a ride on his back for a bit.

They swam in silence during that time, Sanji actually recognizing a few landmarks on the seafloor that indicated their direction, enough that he was able to redirect the wandering shark-man several times when he drifted off course.

Still, Sanji's arms curled around Zoro's shoulders, and he rested his chin there, tail moving less and less as Zoro took over the brunt of the towing, not that he much minded.

Sanji's fingers trailed up and down his chest gently, and Zoro wasn't sure why, but his hand automatically migrated to catch the blond's, lacing their fingers, his thumb brushing Sanji's skin.

He heard a content hum leave Sanji's throat, felt him shift to one side of his dorsal fin, careful not to crush it as he pressed his chest into Zoro's back.

Lips followed that contact, this time behind his ear, the most delicate pressure that shot a pleasant tingling through Zoro's chest, left his skin burning wherever Sanji touched.

"Do you remember Ace?" Sanji murmured close to his ear. "One of the guys I introduced you to the other night."

Zoro nodded, voice gone, but thankfully understanding as he tried to focus on swimming with the added distraction of Sanji's touches.

Sanji shifted a little, and he seemed hesitant to continue his thoughts, enough that Zoro slowed a little, glancing back over his shoulder warily.

"I-" Sanji started, shifting his grip to hold onto Zoro's hand tighter. "He - He knows. About you. About - all of this. I told him."

It took a beat for Zoro to process, translating in his mind and reading Sanji's implications before he _got it._

" _What?!"_ he yelped, using his own language instinctively as he tore from Sanji's grasp and flipped around to look at him.

But Sanji was quick to keep ahold of him, hands clasping Zoro's biceps.

"Mosshead, stop. Listen to me! I _trust_ him! I told him not to interfere, and I know he-" he insisted, though Zoro quickly shook his head and rose hands to push Sanji off him, cutting him off.

"But - _human!"_ he growled, feeling his heartbeat begin to thunder in his ears, imagining every fucking thing that could go wrong. "Not O.H.A.R.A.!"

"I know, but Zoro," Sanji tried again, relentless in his quest to hold onto the other merman, this time with hands on his face. "I trust him as much as you trust - Dr. Nico or - or any of them! Hell, I trust him more because I've known him longer! He's a good-!"

" _And what the fuck will you do if he spreads this, idiot?!"_ Zoro hissed back, again lapsing into his own language for lack of sufficient vocabulary. He stubbornly reached up to take Sanji's wrists, prying his hands off rather easily, confusion, and a bit of despair, now on the blond's features.

Zoro didn't clarify or translate, just glared at Sanji, teeth slowly baring angrily, a show of ferocity that hardly concealed the surprising feeling of betrayal that bubbled within him.

The logical part of him knew Sanji hadn't meant any harm, knew that he still trusted the blond. But the thought of Kuina, the thought that he'd just gotten her back and he did not want to see her taken away again….

It filled him with protective anger, anger that, for once, he was able to hold back, if barely, because that rarely used logical part knew the anger shouldn't be directed at Sanji.

Sanji shrunk back, no longer trying to console Zoro's fury with physical touches, and he managed to keep a frustrated scowl off his face because he was well aware how this looked, how it probably felt to Zoro, who feared losing everything again.

So his next words were an apology.

"I'm sorry, Zoro," he said quietly, keeping his eyes locked on Zoro's, despite the merman's fierce glare. "But I promise. I would never do anything if I thought it would put you or your people in danger. I _trust_ Ace, and I just, after talking with my dad - I needed to…"

He trailed off with a small growl, Zoro watching his face the whole time, watching the way Sanji fidgeted, lifted a hand to rub at his chin anxiously before turning up his palms.

"My dad didn't even want me coming back with you," he explained. "I just needed another ally."

Zoro's heart was still pounding, fists trembling with the urge to fight, but this time, he actively forced it down. He actively forced himself to stick to his belief, that Sanji was different, that Sanji would help, and that they could do this together. He thought back to the previous day, seeing how broken he'd looked, learning about his family.

It would only be more foolish to cut him out now, after everything.

So he slowly drifted forward in the water, Sanji watching him, almost in wary acceptance of whatever he was planning.

And he was right to be wary, because the first thing Zoro did was draw back a fist and punch him hard beneath the ribs, something Sanji took, with a bit of shock and a grunt, bubbles swirling.

Zoro swam through them though, catching the blond by the chin before he could whirl back too far and dragging him in close.

Sanji's features were still twisted in a pained grimace, but he managed to meet Zoro's intimidating gaze again, their faces close. Zoro noticed Sanji's eyes flit down to his lips ever so briefly, but he ignored it.

"Not trust Ace yet," Zoro growled, voice low. "But...trust _you_ …."

The second a wave of relief came over Sanji's face, Zoro squeezed his chin tightly to keep his attention.

"Promise," he insisted again, and Sanji nodded.

"I promise it'll be fine. We can trust him," he replied sincerely, and he didn't budge, even when, after a beat, Zoro pulled his hand away and backed off slowly.

He stared at Sanji for a moment longer before turning tail and swimming off without another word.

Sanji didn't move, just watched him go, his hand coming up to rub at the throbbing spot Zoro had punched, swallowing the panic, the fear that he'd so quickly lost something he'd just realized he wanted. And though the fear and the thought that he'd really hurt Zoro was still there, he had to admit it was appeased slightly when, after a short distance swimming alone, Zoro's shoulders slumped in exasperation and he whipped around to face Sanji with a roll of eyes and an insistent gesture for Sanji to follow.

"Come on, Question," he muttered impatiently, and Sanji allowed his lips to turn up ever so slightly.

"I would, but….it's that way," he answered, pointing back over his shoulder at the two towering columns that rose up in the distance, marking the edge of the trench that led to Noah.

Zoro's eyes focused on them, his brows raising in not-so-subtle surprise for a moment before they scrunched down again and he blew past Sanji with a thump of his tail against the blond's side.

Of course, he also managed to grab hold of Sanji's forearm as he did, yanking him along, and when Sanji's arm slowly lifted to tentatively curl around his, Zoro didn't stop it.

* * *

It wasn't often that Reiju wandered the decks of Noah, preferring the peace and quiet of her private chambers. If there was a problem, others could come to her.

What she'd never admit to was that it had started from fear, fear of the danger that lurked above the surface. Fear that she'd be taken just like her family…

Of course, things had changed in the years since. She'd learned to fight, learned that fear was a weakness and one she certainly didn't want to succumb to.

So even if it was rare for her to ascend to the deck, weave her way around groups of merpeople to the bow, she wasn't afraid to, and it was there she settled for a while that morning, leaning up against the railing, the massive faded orange of the smokestack as her backdrop.

It was calm, looking far down at the trench below, watching merpeople slipping out of the ship's circular windows and swimming off, and then looking up at the bright teal water above, warm and clear with the sun's light.

There didn't appear to be a threat in sight.

And yet, there was apparently one pursuing the three mermen who she noticed swimming some fifty feet away from the boat, their voices echoing in the surrounding canyon that rose up around them.

Her brothers seemed not to have a care in the world, two of them, Niji and Yonji, shoving each other rather roughly, but laughing as they did.

They must have been thrilled to be free, and maybe a good sister would have gone after them, offered to show them around, anything.

But there she sat, watching them silently, arms holding herself and an odd feeling in her stomach that hadn't been there when she'd met Sanji.

She didn't quite know what it was, whether it was one of complete mistrust or what, but it stopped her swimming after them, leaving her to simply stare, brow furrowed in thought as she watched them in the distance.

She was so fixated that she actually startled the second a blond head popped up on the other side of the railing beside her, followed by a green one that hung back.

"Didn't peg you as the type to startle," Sanji said with a smirk that widened when her shock shrunk into irritation, the merman resting elbows on the railing as he hovered there.

"I don't," she answered dismissively, fixing him with an unamused look. "Zoro, I wasn't expecting you to bring him back so quickly."

At that, the two mermen shared a glance, something that surprised her perhaps more than Sanji's entrance when Zoro's eyes softened entirely upon meeting Sanji's, his cheeks reddening a little.

" _Yeah, well…after the shit that happened last night….he needed to talk to you,"_ he muttered in their own language before adding, " _M'gonna go look for Kuina…"_

And he almost swam off before Sanji grabbed his wrist and stopped him, tugged him closer gently.

"Uh…" said the blond, flicking eyes to his sister. "If you'll excuse us a moment."

Then he darted down out of view, rounding the corner of the bow and diving lower out of sight, dragging Zoro with him.

Reiju blinked, raising a brow slowly at the odd display, fingers tapping against the railing for the long minute until the both of them popped up again, Sanji with a satisfied smile and Zoro with more fluster on his features than the mermaid thought she'd ever seen, his face flushed and lips a little swollen.

" _Yeah, just…gonna go look,"_ Zoro mumbled again, meeting Sanji's eye one more time before nearly ramming himself into the rail to get over it clumsily. Then he finally swam off across the deck towards the doors to the great hall before veering a hard left and disappearing down the starboard side of the ship.

That weirdness aside, when Reiju glanced back at Sanji, the merman was still staring after Zoro, running a hand over his mouth to suppress the stupid grin that wanted to grow on his face, biting his lip before finally looking back over at his sister.

He caught the deadpan look on her face though, instantly asking, "What?"

She shook her head, erasing all weird images that threatened to assault her mind.

"I don't wanna know," she muttered.

Sanji snorted.

"You're right. You don't," he agreed, pulling himself up the rail a bit to hang arms over the top. "Anyway, our brothers? What the fuck? They're alive?"

It brought her right back to the moment she'd been lost in before he'd shown up, the three mermen still in view, venturing out from the ship.

She wasn't surprised Zoro had told him, and she turned her gaze back to Sanji, whose eyes were full of curiosity and excitement….which slowly began to fizzle when she didn't express even wry amusement.

"What's wrong…?" he asked warily, smile falling a bit.

"Whatever your expectations are, lower them," she said, her brother's brows predictably furrowing.

"What do you mean?"

"They're not…."

She trailed off, not even sure how to describe the strange disappointment she'd felt, seeing their sneers, feeling their disinterest when it came to their history, beyond the fact that they were princes.

"Not what…?" Sanji pressed.

 _Like you,_ she automatically thought, but instead she merely let the question linger, lifting hands from the rail and straightening, tucking a stray lock of hair back behind her ear, only to have it float loose again.

"Nothing. I'll introduce you," she said, and gestured for Sanji to follow.

* * *

Waking up to an enclosed space wasn't new for Kuina.

How many times had she hidden herself in the small artificial caves of the shark enclosure when Sakazuki had left her there for days on end? She'd hidden herself and dreamed of this very ship, of these rooms which had been her home, the merfolk who had been her friends, her family, when sharks were so often abandoned, her and Zoro left by their own parents at a young age.

Their parents had been from nomad clans, and it was part of why the two of them had stuck together when they were young. They had no one else.

So she'd dreamed of these labyrinthine halls, of the thrill of trapping prey inside, dodging old furniture and swinging doors to chase it through room after room. She dreamed of the open ocean, that endless blue, of the pods of humpback whales that migrated through East Blue every year, slow and graceful.

She'd dreamed of the dolphins, whose clicks and calls could be heard in the night, of that time she'd dared Zoro to hitch a ride on one, and how dumb he'd looked flailing through open air when it had leaped out of the water to throw him off its back.

She'd dreamed of this shit, and that had been her curse, more so than the princes, _knowing_ what she was missing, _knowing_ what was out there, but unable to get back, or move on.

And now she _was_ back, and it felt like an entirely different world, one she wasn't expecting to feel this removed from.

The sunlight danced across the ceiling of her room in slithering patterns, Kuina's eyes studying the light fixture that used to be more gold than rust, but was now the opposite. There was a gaping hole in her ceiling now, leading up to another room on an upper floor. Even her bed had deteriorated over the years she was gone, so that the mattress was in tatters, bits of old fabric wisping up around the edges like the tendrils of a jellyfish.

Her eyes had drifted to the porthole, where, outside the window, she could see the occasional merperson swimming by, many on their way to hunt, some out to stretch their fins in the morning light. She had no idea who any of them were...

And then her eyes had fallen on that white sword, propped against the wardrobe on the opposite side of the room, where it had most likely gotten swept by the water's movement and stayed lodged.

She could see the way barnacles had grown around it on the wardrobe's surface, so much so that when she swam over and found her hand clasping itself around the sword's hilt, she pulled it back to see a near-outline of the blade's shape, clean of the little crustaceans.

It was light in her grasp. She could easily lift it, give it a few experimental swings that were controlled and fluid.

She'd reached that point, it seemed, reached that goal she and Zoro had set for themselves all those years ago, the desire to grow in strength, to swing the blade like it was nothing.

And it was particularly apparent when she heard movement from above, a figure suddenly sprouting out of the hole in her ceiling, sudden enough that she instinctively whirled around, both hands clamped on the sword's hilt, full intention to strike.

" _Oi, what the-!"_ Zoro screeched, barely dodging, a swipe of his tail taking out another foot of ceiling, sending the material crumbling and floating into the room in a white cloud.

"Fuck! _Zoro?"_ Kuina yelped, pulling the blade away quickly in a flurry of bubbles and throwing herself back to avoid him. "What the fuck are you doing?!"

He rolled out of the way, straightening himself with a scowl, a hand lifting to rub bits of ceiling out of his hair before lifting his eyes to her, eyes that averted a little dejectedly a moment later.

" _It's still weird as hell to hear you speak human language, y'know…"_

She blinked, surprised to actually understand the gist of his sentence, enough that she looked away sheepishly, eventually shooting back, "That doesn't answer my question. Why are you falling out of my ceiling? There's a door."

He glanced over at it, shrugged, then muttered, " _The hallways change."_

Their eyes met again, and a palpable awkwardness filled the air, both remembering how the previous night had ended, far too emotionally for both of their tastes, even if it was entirely warranted after so long apart….after assuming each other dead.

Zoro's gaze fell to the sword, still in Kuina's hand, looking at it for a moment before his lips turned up.

" _Can't believe that thing's not covered in sea anemones by now,"_ he mused fondly, glancing at Kuina again, only to find confusion on her face, mouth working for a reply, but it was clear she didn't understand him.

He squashed his disappointment, unable to stop his smile from falling just a little, instead saying, "I - let's go - outside? Hunting?"

Zoro saw the way her lips quirked ever so slightly, enough that he wondered if she'd laugh at his sorry excuse for human language.

But instead, she pushed the sword towards him in the water, turned to grab a strange human bag from the floor near the bed, onto which he realized a few knives were attached.

She threw the pack over her shoulder and grinned.

"Let's see who's better now."

He couldn't help but take that sword and match her grin.

* * *

 _ **O.H.A.R.A. - West Blue**_

* * *

The morning sun had been up a mere hour, but already it blazed with growing heat, preceding a scorcher of a day.

The paper cups of coffee Robin carried on a small tray across the docks were steaming as well, sounds of preparation already underway aboard Smoker's boat when she approached.

The two young men, Coby and Helmeppo, were scurrying about, running routine maintenance checks with far more nerves than usual. The small crew had slept on the boat, though Robin had offered them space inside the lab, and it was probably for the best because the two already looked like they'd been up for hours, anxious to get going, judging by the ropes they were each tying and re-tying to kill time.

"Good morning~" Robin called out, deep purple water shoes stopping just in front of the short gangplank.

Coby and Helmeppo both stopped their work, eyes falling to the tray of drinks hungrily for a second before Coby broke into a smile first.

"Good morning, Dr. Nico," he greeted, Helmeppo lifting his sunglasses briefly to give a nod too.

"I've brought coffee for your journey," Robin said, indicating the cups she carried.

Coby smiled gratefully and led the charge across the deck to retrieve a cup for himself, taking a tentative sip through the lid, Helmeppo following suit.

"Dr. Nico - _ow!"_

A sudden yelp and a thud from the hatch leading to the cabins below deck, Tashigi poking her head up, only to knock it against the ceiling, the woman rubbing at her sore temple, glasses askew as she ascended the narrow stairs.

"Good morning," Robin said again, a smirk on her face as she offered Tashigi a coffee as well.

"Thank you," Tashigi replied, taking the cup in both hands. "My head's already throbbing thinking about the talks we'll get at HQ today…."

"Pretty sure it's 'cause you banged your head," Helmeppo muttered under his breath.

The click of a door and out came Smoker, emerging from the navigation cabin, not one but two cigars already clenched between his teeth. He wordlessly pushed past his crew and descended the gangplank to take a coffee from Robin too with a silent toast of thanks.

"When will you be setting sail?" Robin asked.

"Any time now," Smoker answered with a pointed look to the others, Coby and Helmeppo already slinking back towards the deck once more. "You?"

"Soon as well. We'll be following your course. Dr. Brook will contact B.A.R.A.T.I.E. Chopper will cover things here. Right now, we're also waiting to hear from Nami," Robin explained as the sliding of the automatic doors to the main building sounded behind her, Franky stepping out, clad in a small pair of wetsuit shorts and yet another open floral shirt.

"Ah, yes, did the girl make it to the Naval Base?" Smoker asked, Franky's bare feet on the dock getting closer before he came to a stop beside Robin.

"That was her just now," Franky answered, the man waving his smartphone, dwarfed in his large hand. "She got a call from her mom 'fore she even got there." He sighed, looking at the group more seriously. "East Blue Navy _knows_. And - well, I guess that means West Blue does too."

A yelp from onboard the boat, Tashigi's eyes going wide behind her glasses, the woman nearly dropping her drink.

"About the - about _everythi_ -?" she started to ask, but Franky was already nodding.

"Uh huh," he confirmed.

He reached out to rub his hand over the small of his girlfriend's back when Robin slipped the empty tray beneath her arm and brought a hand to her chin, a subtle but clear indication that the news had troubled her.

Smoker's voice was low and irritated when he spoke up, crossing arms over his chest and trying hard, it seemed, to keep from crushing the coffee in his gloved hand.

"How?" he asked. "Who told them? Was it Zeff?"

"She didn't say," Franky replied. "Only that one of Whitebeard's commanders spilled it. Dunno how _he_ found out. Whitebeard called the M.A.R.I.N.E.S. but, go figure, no answer. Both bases're gonna send ships out to HQ. Think that's our cue to get out there too."

Robin was nodding immediately, her mind traveling to the voicemail from Sanji that was still on her phone. The one she'd purposefully ignored the day before because she'd trusted Zoro, or preferably the Queen herself, to answer any questions he might have had.

But now she worried. She worried because there had been no word from Zoro, only this news of the M.A.R.I.N.E.S. advancing, of the captive merpeople escaping….

Zeff wasn't looking to help.

And now the Navy suddenly knew.

All of it pointed to a potential leak of information from _Sanji_ of all people….

Despite the concern and burgeoning disappointment brewing within her, that Franky could no doubt sense, as his fingers had started moving again over her back, she merely sighed and agreed, "Yes."

"We're going now," Smoker announced, turning his head to nod at Coby and Helmeppo, who immediately scrambled to get ready once more. The man's dark eyes bore into Robin's before he asked, "The coordinates for the colony?"

They'd talked about it the previous day. Smoker had wanted to go straight to the source, to make sure the M.A.R.I.N.E.S. didn't cause any trouble. She'd decided to trust him and his crew. But this was the first time she'd been faced with the choice of revealing exactly where the merpeople lived.

She had to believe everything would be fine. They were running out of options, after all.

Robin glanced over at Franky, the two of them sharing a brief moment of understanding, in which Franky gave an encouraging nod and a tiny smirk.

Robin returned it with a little tilt of lips.

Her eyes lingered on Franky for a long moment until she answered, "Alright."

* * *

 ** _Noah - East Blue_**

* * *

The fact that Reiju told him to "lay low" as they approached the three mermen who were apparently his brothers wasn't exactly a comforting thing. Sanji couldn't understand why she hardly seemed relieved to have them here, hardly seemed happy at all when they _should_ be celebrating, even if their mother had still been lost.

But as they approached the three, now some distance from the ship, skirting along near the sandy bottom of the trench, Sanji began to get a feeling why.

At first glance, the three didn't look related, hair and tails all completely different colors. One had a blue tail, but it was much lighter than Sanji's, far more turquoise. The only indication that they did have some relation was the fact that they shared a species, evident by the long caudal fins that twirled in the water behind the two that wrestled and shoved each other playfully as they swam.

There was nothing wrong with the scene, and in fact, it was a little amusing to see two of them wearing sunglasses when the brothers noticed Sanji and Reiju's approach, the three slowing and glancing back over their shoulders.

But none of them broke into smiles, their expressions only growing more stoic and serious, and suddenly an uneasy feeling began to form in Sanji's gut.

It was Reiju who spoke up first, composed, her arms crossed over the light pink top she now wore, lacy cut-outs exposing her bare back. Sanji honestly wasn't sure where the merfolk got their clothes from, though that hardly mattered in the moment.

"Am I interrupting?" she asked.

The redhead answered, his tail a rather shocking shade of crimson, almost appearing soaked in blood.

"Nothing but their roughhousing," he replied seriously, voice nearly deadpan. "To what do we owe the pleasure?"

The redhead flicked eyes to Sanji, clearly noticing him, as did the other two, who hung a little farther back. Their stares were uncomfortable though…. He felt….judged….

"Did you sleep well?" Reiju asked, the moment a little awkward as the question was quite obviously a mere formality, her own expression stoic as well.

Her question went entirely ignored, however, as the brothers' stares didn't let up, merely intensified in the moment that followed.

"Who's that?" asked the blue-haired brother finally, and his tone was far more biting than curious, almost enough to make Sanji wince.

He resisted though, instead sharing an anxious look with Reiju, who wore her weariness all over her features. There was no use hiding the truth, after all, and Sanji could tell she knew that too.

"Sanji, this is Ichiji, Niji, and Yonji," she introduced, indicating each. "All of you, this is-"

"We know who he is," Yonji interrupted coldly, cutting her off, Niji's lips curling into a barely-disguised sneer beside him.

Sanji's heart jumped a little, for a moment wondering how the hell they would know him. But there were many ways, he supposed, and clearly none of them had left a good impression…

As such, he was a little surprised when Ichiji swam forward after a moment, his eyes concealed by his sunglasses, but his hand outstretched in a familiar greeting. The atmosphere was still tense, however, enough that Sanji's returning handshake was slow and wary.

And rightfully so, because as soon as he'd clasped his brother's hand cautiously, Ichiji yanked him forward hard in the water, reaching out and grabbing his wrist, turning it to examine the metal band encircling it.

"A bracelet," he muttered, tone unreadable. "So you can't transform at will."

Sanji frowned, unsure if that was the story they'd been told, and shook his head.

"I….no," he answered. "All of this. I only just found out in the past few days…"

"You've only known a few days..." Ichiji replied with a humorless laugh, and with that, he turned back to the other two mermen, ending the interaction. He shot a glance at Reiju as he did. "We're off to do some hunting. Unless you had other business with us."

The mermaid shrugged blankly.

"You're free to do as you wish," she said, but she'd hardly gotten the words out before Sanji balked, especially when the three brothers began to swim off once more.

"Hey - hey, wait!" he called, unable to stop himself. "What about-? The M.A.R.I.N.E.S. are after you! Do you really think you should be-?"

"What we do does not concern you," Ichiji replied over his shoulder dismissively.

But it didn't deter Sanji. It couldn't, not when he still had things he wanted to say, even if his brothers obviously wanted nothing to do with him.

He couldn't blame them, not after all they'd been through, not after living the life he had, unaware of their plights. Maybe it wasn't his fault, but it didn't change the fact that he felt _guilty_ , dammit, and now he actually had the chance to atone for it. His brothers were alive, and they deserved to hear it, just as his sister had.

"Oi-! Would you-? Wait!" he called to their retreating forms, ignoring the way Reiju's head whipped around, imploring him to stop with a pointed stare. Instead, he swam after them. "I wanted to apologize! I wanted to tell you that I'm-!"

His words were effective, because not a second later, Yonji turned around quickly, a look of growing frustration on his face.

"Would someone shut him up already?" he complained, throwing arms up. "Y'know, you got some nerve actin' all casual like this! Like you actually give two shits about us! Living your great life, oblivious to everything right under your stupid nose!"

There it was, what Sanji had feared they'd feel. Of course, he'd hoped for forgiveness, but how could he expect it when this was their reality.

But if he didn't try, what use was he as a brother? So, he renewed his convictions, tried to look past the growing fury on his brother's features, features that were so similar to his it was like looking in a distorted mirror, at his own anger...how he'd felt the previous night talking to his father.

Maybe he couldn't understand their experiences, but he could understand their feelings.

"Of course I give a shit!" Sanji shot back. "You're my brothers! You're - we're - we're _family!_ And maybe I didn't know until now, but that doesn't mean-!"

" _We_ \- are not family!" Yonji implored, gesturing between the two of them. Ichiji and Niji had slowed as well, the two hovering a few tail-lengths back to observe the argument. " _You_ haven't done fuck all for us! No one even _thought_ to come after us!"

"Because everyone thought you were dead!" Sanji insisted, knowing it wasn't much of an excuse, giving up like that, but surely it was something.

He looked back with desperation to Reiju for support, but his sister merely floated there, gaze downcast and brow furrowed. He was on his own, he realized with an exasperated sound.

Stubbornly, he turned to face Yonji again.

"Look - I can help!" he tried. "I want to! I can - I want B.A.R.A.T.I.E. to-!"

"Don't even bring up B.A.R.A.T.I.E.! You _work_ for them, you bastard!" Yonji cried, closing the distance between them. Sanji struggled not to let his brother's bulkier size intimidate him. "You think you're any better than the M.A.R.I.N.E.S.? Fucking traitorous-!"

"I'm _not -_ if you'd just-!" Sanji interrupted, reaching out to just barely skim fingers over Yonji's arm before the merman yanked it away.

"Get the _fuck_ away from me!" he spat out. "Don't you dare touch me, you filthy human!"

It stung, even if it was something Sanji never expected to hear directed at him as an insult. It stung, particularly when Yonji darted back away from him, as if his very touch was painful.

Frantic noises started to leave him, growls and hisses that sounded feral, Yonji's fists clenching and his movements becoming more erratic, particularly when a flick of his tail sent him banging back into the rock wall beside them, something that merely made his eyes flash inhumanly, teeth baring in a sharp grimace.

Something was changing in him, and for a moment, Sanji couldn't understand what, particularly when the merman started shouting again, despite Sanji now keeping his distance.

"Stay away!" he yelled, backing into the wall once more, then again, almost as if he'd forgotten he'd done it, lost his depth perception. "Stay the _fuck_ away - don't touch me!"

Sanji's mouth gaped for words, though he said nothing, even as Yonji lifted a tense fist.

Then, to Sanji's shock, the merman punched himself hard in the temple.

Not once….not twice, but several times, his growls becoming more frantic until the noises that began to leave him were more panicked moans and whimpers than anything.

"You're not - we're - we're princes!" he justified, despite no one questioning it, still driving his fist over and over into his head. "We matter! We fucking-! We're stronger than you'll ever be and-!"

"Oh, now you've done it, bastard!" Niji growled from somewhere over Sanji's shoulder, a blur of blue movement advancing upon him in his peripheral, but there was a flash of red that stopped him.

And even if the mermen had shown him nothing but animosity in the short time they'd interacted, a pang still shot itself through Sanji's chest. He couldn't take his eyes off Yonji, and it _hurt_ , dammit, because whatever had triggered this reaction was deeply rooted in something else, something that wasn't taking place in the present.

Sanji was sure of this when he moved towards his brother carefully, only able to utter a gentle, "Hey," before Yonji shrunk back in a flinch and lashed out instinctively with his tail, whipping it blindly but powerfully, the sting of the tip scratching Sanji on the chest.

"I don't - want this - fucking - _stop!"_ Yonji hissed, voice breaking, and his fingers shifting to grip at his hair tightly, knuckles turning white. His eyes squeezed shut and he curled in on himself, sinking to the sea floor with a puff of cloudy sand. "Stop it! I'm done! I want out!"

Nobody moved. None of his siblings moved to do anything, but Sanji wasn't deterred, not even by the throbbing red welt that now decorated his sternum.

He swam closer again, watching his brother carefully for any sign that he'd attack, keeping his voice low and his hands to himself as he did.

"I know," he murmured over Yonji's small panicked whimpers. "I know, hey. Hey...you're okay. You're out of there. It's over. It's over…"

What had happened? What had happened to them over the years to mess with a strong-looking guy like Yonji so much? What had happened that prevented all three of his siblings from swimming forward to comfort him?

What pain had they all been through that left them feeling so isolated…?

Sanji couldn't imagine. He was fortunate enough that he didn't have to.

But that was exactly why he knew he should take responsibility, show the compassion that his four siblings had so missed in their lives….

He made it to Yonji's side without incident, curling his tail and settling himself down on the sand next to him, facing him with eyes that were burning, despite the cool water around them.

He studied Yonji's face, cast with the palest blue and screwed in a grimace.

There were scars there, he noticed for the first time, faint ones, raking down his cheeks in parallel lines…..like the tracks of fingernails.

When his gaze roved downwards, he noticed more on his arms, some of which looked like badly healed puncture wounds, the skin white and gnarled. He caught a glimpse of a fresher one, still red and irritated, much like Zoro's had been, slicing itself across his forearm.

"I'm sorry…." he murmured again, and he lifted a hand to delicately place it over his brother's, which had begun to pull and twist in his hair with greater vigor. Yonji didn't stop him this time, and the blond was able to slowly guide Yonji's hand away from his face, first one, then the other.

"I'm so sorry…..I wasn't there. I didn't know…."

His voice was calm, but it held his regret, the burden he felt from his own inaction, particularly with Yonji's hand shaking beneath his, the merman still struggling to hide from the world behind tightly closed eyes.

"You're right," Sanji continued, curling fingers around Yonji's more securely, giving a squeeze. "You are stronger than me. All of you. I don't - know if I could've gone through what you did…"

Maybe he could have. Maybe he could have survived. But how would he be different? How much of himself would be lost?

How much of his siblings was lost?

"But you're free now," he said, the one comfort that still persisted. "You're free - it's over, and I'm gonna make sure they never take you back. They're not gonna hurt any of you ever again."

The water was quiet, nothing but a faint rush in Sanji's ears, like a second heartbeat that persisted, somehow holding all of them together in its calm.

Yonji's noises had begun to quiet, and Sanji hoped this was a sign that his head was clearing, bringing him back to the present. His gills took in bigger rushes of water, eyes slowly opening but staring blankly down at his tail.

"And how are _you_ gonna stop it…?" one of the brothers asked from behind Sanji, the blond noting it was Niji when he glanced back.

The merman's arms were crossed over his chest, small indents in his skin from where fingernails had dug themselves. His face was passive, but the quiet to his voice and the slight tremble gave away his emotion.

Sanji watched him, tried to meet his gaze beneath his sunglasses.

"My old man and I have been wanting to combine our research organization with the M.A.R.I.N.E.S. and O.H.A.R.A. So we can work together more easily and keep Sakazuki in check…" he explained. "Make it an…. _All_ Blue sort of situation. I know it won't be that simple….but we've gotta start somewhere…"

No response from Niji, no agreement...but also no dissent, no scoff or skepticism. He stayed quiet, his brow furrowing.

Reiju's gaze was downcast too, though her eyes flicked to Sanji as soon as he said that, then to Ichiji when he shifted.

"So what will you do?" asked the redhead.

The blond felt Yonji pull his hand out from beneath his, the merman lifting it to rub at his eyes.

"First, talk to Sakazuki," Sanji answered, watching Yonji for a few moments. "Make sure he-"

"He'll only try and take you," Ichiji cut in. "He's talked about you for years-"

"Let him try," Sanji insisted stubbornly. "I'm not afraid of him… This doesn't make up for what any of you went through. But I don't want you to be in harm's way."

The minute that followed was awkward in its silence, but mostly because, again, no one challenged Sanji's sincerity. In fact, they seemed to accept it, if warily, particularly Yonji, who lifted eyes to him slowly, his gaze tired, but no longer blind with fury.

There was something vulnerable there, vulnerable and maybe a little hopeful, if Sanji dared to imagine it.

Surprisingly, it was Reiju who spoke next, with barely masked concern.

"I'd feel better if Zoro went with you," she said, and though the atmosphere was still serious, Sanji nearly laughed. As if he had much of a choice when it came to Zoro.

He kept his lips from twitching up too much though, replying, "If they try and pull anything, Zeff will have the authorities after them the second he realizes I'm gone-"

But then, a quiet scoff from Yonji, and Sanji winced. Probably not the best thing he could've said, given the fact that no one had gone after his missing brothers…

"And if nothing else, anything they do to me - it'll be a price I'm willing to pay. So long as you never have to go through it again," he remedied.

This seemed to settle Yonji some, his expression simmering back into an embarrassed sulk.

Sanji's eyes couldn't help but fall to his brother's scars again, just briefly, before they shifted to Ichiji and Niji. He wasn't close enough to see if they had similar markings, but it didn't matter. They had wounds inside and out, and now was the time to fix that.

The blond straightened his tail and offered a hand down to Yonji, the green-haired merman staring at it for a long moment before he took it slowly and floated up off the sandy floor as well.

Sanji managed a tiny smile before murmuring once more, "I'm sorry."

One last look at all of his siblings.

"No one follow me," he said with finality.

Then he released Yonji's hand and swam off towards Noah.

* * *

Zoro didn't know anything about Kuina's life in captivity, but it definitely hadn't impeded her hunting skills.

He _never_ thought there would be a day when he would once again dart through the reefs with her as adults, bursting through the tornadoes of shimmering tuna to feed, competing to see how many they could snag with bare hands and teeth alone.

He'd stopped trying so hard after the initial ploy to impress his long-lost friend with his improved strength. Instead, he'd been content to observe, watched as she too seemed to forget about the hunting in favor of gliding through the open sea with sheer joy, a wide smile on her face when they cut through familiar coves, reached the sprawling field of rocks that was still impressively vast, even if they were no longer children.

It was like watching Sanji's first swim, that same awe and excitement, but quieter as Kuina no doubt remembered that time they'd tried to make human weapons out of driftwood on the very boulder she now ran fingers over. She no doubt remembered the painful sting of the anemones' barbs firsthand, which was why she skirted around them now, instead swishing through the smooth tufts of sea grass that brushed their skin.

It wasn't hard to imagine what she was thinking when she finally stopped and perched on a large rock that no longer dwarfed them in size, slipping off her backpack and settling the sword beside her.

Zoro slowly came up to her side as she sat, gazing out at the great expanse of water before them, the schools of fish that swam in the distance, specks in the otherwise uninterrupted blue.

They were both quiet for a long time, enough that it afforded Zoro the chance to study her, to notice the healing wound on her arm, the other scars that peppered her skin and tail.

His own tail was far from perfect, marred and weathered with bite marks and slashes alike, but he was certain she hadn't gotten hers from fighting prey, not when she'd been held in a place where there _was_ no prey.

"I missed this," she said quietly, interrupting his thoughts, though it took him an extra moment to move his gaze, from a particularly long slash on her upper arm, to her face.

Her eyes had flicked to his, and despite a tiny nostalgic smile, she lifted a hand to brush over the scar he'd just observed.

She knew he'd been staring.

 _"I'm sorry…"_ Zoro murmured automatically, for some reason finding it difficult to use human language with her when she was of merfolk like him.

Kuina understood that much though, frowning and turning herself to better face him.

"For what…?" she asked.

Her question came in human language, but he still answered in his own, frustration filling him over his own inability to form proper words in either language.

How could he express what he felt? The stupid fact that his own relief had begun to morph into guilt the longer he studied those scars, thought about all she had missed out on, the horrible things she must have experienced.

At least….and it was an awful thought….but at least, if she'd really died, she wouldn't have been subjected to a life in captivity.

" _I shouldn't have - shouldn't have accepted you were dead,"_ he expanded, feeling a tightness tug at his chest. " _I should've - come after you. I should've tried to-"_

His speech was broken, but her eyes still narrowed with understanding, picking up keywords necessary to his meaning.

"Zoro, you were ten years old," she justified. "We didn't know….anything. There was no way we could've fought back. It wasn't like I was waiting for you to come save me. I thought….for sure they killed you too."

This admission was a difficult one, the fact that she too had given up for a long time. It was difficult, but maybe it would be comforting to Zoro, to know that he wasn't the only one who'd thought the worst, even if they'd known how strong they both were.

Kuina thought hard, pulled up long unused language in her brain to say, " _It's okay,"_ hoping it would hit home harder than human language could.

It did strike a chord in Zoro, however small a gesture it was, the familiar and comfortable words filling his chest with a strange warmth, leaving him unable to form words in return for a good minute.

Finally, he was able to mutter a somewhat sulky, " _Yeah, but….they hurt you,"_ that was starting to sound like foolish logic in the face of Kuina's insistence.

She rolled her eyes.

"Better me than the princes. I'm just a mermaid. I'm expendable."

He frowned with confusion.

"Ex….penda…?" he struggled to repeat, not understanding.

"Expendable," she repeated with a smirk. "I-"

Then she seemed to think otherwise, and tried once again to dredge up the clarifying words from the depths of her memory.

" _My life...below….princes-"_ she said, displeased with how broken it sounded.

Immediately though, Zoro's eyes widened and he interrupted her.

" _No, it's not,"_ he cut in. " _What are you talking about? Did the M.A.R.I.N.E.S. tell you that-?"_

" _Yes, but-"_ she tried again slowly. " _Know - knew it - before…"_ A growl of frustration and she gave up, switching back to human language. "There's not much importance in a mermaid like m-"

" _When have you ever thought that? Kuina, what the fuck?"_ Zoro interrupted again, surprised to hear this coming from _Kuina_ , and for the first time since their reunion, there was a painful feeling in his gut….a feeling that maybe things really had changed more than was apparent on the surface.

Maybe the wounds inflicted by the M.A.R.I.N.E.S. weren't just physical….

"Don't _what the fuck_ me, Zoro, look at you!" she cried, gesturing to him insistently and roving eyes up and down his form. "Look what you became! Shit, if we tried to fight now, it's obvious who would-"

"Shut up!" he blurted out, and Kuina's eyes went wide with surprise at his usage of human language. But he couldn't help it. He hadn't understood everything Kuina was saying, but her tone and adamance was enough to tell him she was still protesting.

"Kuina, you - you were-"

He growled, unsure why his language skills seemed to disappear in the presence of his friend, and lapsed back into his own language.

" _Mermaid or merman, you were always stronger than anyone! The princes - the Queen - their lives matter, but you - you-!"_

Zoro didn't know what the hell he was getting at, only that it was taking him dangerously into feelings he'd long pushed aside and suppressed, lest the loneliness consume him. He hadn't wanted to be like Reiju. He hadn't wanted to lock himself in a room for days, isolate himself. He'd wanted to get out, get stronger.

When O.H.A.R.A. had deemed it safe and released him back to the colony, he hadn't wanted to admit to his pain or his fear. He was a tiger shark, for fuck's sake. He didn't need anyone.

But he'd been young, and those morose feelings wouldn't go away, especially when he remembered so clearly, even now, Kuina calling for him in her panic and terror.

" _You were my best friend,"_ he eventually muttered, looking away to study a trail of scalloped clam shells scattered in the sand. " _And thinking you were gone, just….it fucked me up. It fucked me up real bad…"_

Again, Kuina's surprise was obvious, hearing Zoro admit to things she never expected to hear from him. She remembered a prideful little boy, annoying and headstrong, who would sooner make fun of someone for getting sappy than let emotions affect him.

But there was genuine pain in his voice, and considering how uncomfortable it was for her to see, she had to wonder if this was how she was making him feel with her own insecurities.

"Zoro…" she murmured. "You didn't think this was your fault, did you…?"

He didn't answer, just floated there with his arms crossed, his tail giving an agitated flick.

"Zoro-" she pressed.

"M.A.R.I.N.E.S.' fault, but - should have - should have looked - for you…." he stuttered out.

And it was back to this, enough that she pinched the bridge of her nose and muttered, "You idiot…"

But it wasn't just to him….because hadn't she thought the same thing…?

" _But that's why I'm sorry…"_ he said, and Kuina decided she'd had enough. They were both here. They were both, by some fucking miracle, safe and free, and any more of this stupid self-deprecating shit would do them no good.

So she pushed off her rock and swam over to him, grabbing his head in her hands and squeezing his cheeks to stop his brooding, just like she would when they were children.

"Stop. No more. Erase it," she ordered. "I don't like seeing that look on your face."

Zoro quirked a brow in surprise, stayed frozen there for a moment in his shock.

But then he lifted a hand to swat her away, ultimately swishing his tail for a light smack to her side when she didn't immediately let go.

" _Fine,"_ he conceded, ignoring the amused smirk on her face. _"I'll erase it by making sure none of this shit ever happens again."_

"And how are you going to do that?" Kuina asked, hoping she was correct in inferring his meaning.

"Got help," he answered smugly in human language, because, after all, he'd been the one to start all this. He'd chosen an excellent day to fight with boats.

Kuina wasn't certain of what he spoke initially, but a quick replay of the meeting with Reiju the night before was enough to refresh her on the very recent events that had apparently occurred just before she and the princes had returned. Events that made her more nervous than glad.

"Sanji," she deduced with some hesitation, knowing she'd gotten it right when he nodded and gave a pleased smirk.

Of course he fucking worried about what the M.A.R.I.N.E.S. would do to Sanji. But that blond was stubborn as fuck, and he had enough support from the humans that if they tried anything, there would surely be hell to pay. Not to mention, he had a bracelet. He could-

"I have something too," Kuina said, swimming back to the rock and unzipping the front pocket of the backpack she'd plopped down onto it.

And Zoro's jaw dropped to see her holding a bracelet identical to the one he'd gotten from O.H.A.R.A.

For a split second, he panicked, worrying it was Sanji's and he'd find the dumb human drowned at the bottom of the trench somewhere. But what little common sense he had brought him back from that.

" _Wait...what?! Where the hell did you get that?!"_ he squawked, only to have Kuina roll her eyes dramatically.

"Weren't you listening yesterday?" she asked. "I stole it from the M.A.R.I.N.E.S. I used it to help us escape."

He hadn't been listening, not only unable to understand the majority of the conversation but also just a bit preoccupied with seeing his childhood friend essentially back from the dead.

As such, his only reply to Kuina now was a series of unintelligible noises that made no sense in either language.

She stared at him for a minute, but when it seemed he wasn't going to converse normally, she shot him a look of exasperation.

"Obviously, I kept it," she said. "I was meaning to return it to the Queen, but with everything yesterday, I dunno. It wasn't the right time…"

" _Damn…"_ Zoro finally managed, lifting a hand and running it back through his hair. " _So if O.H.A.R.A. had one….and the M.A.R.I.N.E.S. had one… What happened to the last missing one?"_

"What?" Kuina asked, confused, so Zoro clarified, "Last one - where?"

"Don't know," she replied, shrugging. "The M.A.R.I.N.E.S. don't have it. I was able to get that much out of some of their grunts."

" _Damn…"_ Zoro muttered again, for lack of anything better to say. It was probably safe to assume that thing was at the bottom of the ocean somewhere, lost in the past conflict.

"Hey, speaking of which…." Kuina said, suddenly straightening into a more formal stance, and Zoro furrowed his brow when she cleared her throat pointedly and jerked her chin at something behind him.

He turned...and nearly broke into an excited grin automatically before he remembered to reel it back in to a more subtle smirk.

Because there was Sanji, or at least, a small blond blob, approaching from a distance.

He shot a glance back at Kuina, amused by her rigid form, the respectful posture she'd always assumed around the Queen, one he was _certain_ she needn't strain herself with around the Question. Even if he was technically royalty.

" _He's just an idiot. You don't gotta do that,"_ Zoro assured, snickering when her jaw dropped at his insolence.

Sanji was within earshot now, the blond raising a hand in greeting and calling out, "Hey, mosshead!"

Zoro hooked a thumb over his shoulder to indicate the proof of his statement to Kuina.

"Hey," Sanji said again as soon as he reached Zoro's side, his hand reaching out to brush fingers at the small of his back before he seemed to think otherwise of the physical contact upon seeing who he was with, pulling his hand away.

Zoro didn't mind either way, though he had to admit Sanji looked damn good with a flush on his cheeks after a long swim.

Sanji was already eyeing Kuina, the mermaid having started into a bow, just getting out, "Your Highne-" before Sanji frantically flailed arms in protest.

"Aaahhh, no, it's okay!" he assured. "It's - I'm not-!"

Then, a short sound of frustration before he jutted out a hand towards her with a more relaxed smile.

"I'm Sanji. And you're….Kuina, right?"

She nodded and took Sanji's hand tentatively, giving it a shake of her own.

As soon as she released him, Sanji thumped his hand back into Zoro's chest, leaning in to grumble, " _You're_ supposed to do the introducing, Mr. _Mutual Friend."_

"What?" Zoro said dumbly.

"Hopeless," Sanji muttered, shaking his head. Instead, he turned back to give his attention to Kuina. "I know - we don't know each other, but - I heard about what happened to you and - well, I'm glad to see you're alright."

"Thank you," she replied quietly, tucking some hair behind her ear anxiously and bobbing her head in a submissive gesture again, hardly making eye contact.

Sanji's lips tilted up more, but when he glanced at Zoro, the other merman had a frown on his face, his brows drawn in and head tilted as he looked at Kuina strangely.

He said nothing though, and Sanji decided he wasn't going to question it in that moment. There were pressing matters at hand.

"Um," he started. "Listen, I - Zoro, I wanted to talk to you, but Kuina, since you're here, maybe you can give me some advice?"

Despite her nervous demeanor, the mermaid couldn't keep her own brows from tensing slightly.

"Advice with what…?" she asked slowly and he gave a light chuckle.

"It's probably best if we sit down," he said with a squeeze to Zoro's bicep before he started to swim towards a larger rock a short distance away, one where they could all settle.

As soon as he turned his back, Zoro was shocked to feel Kuina's hand clamp down on his arm.

" _Zoro. You….sure…..?"_ she hissed quietly, the fact that she didn't use human language proof she didn't want Sanji to understand her. " _Believe - no….trust him?"_

She knew it wasn't fair to blame Sanji for anything that had happened to her. But he was still a human, and her experience with them had been nothing but terrible.

Zoro had been her closest friend, one of her _only_ friends in her life. Despite assuming him dead, the thought of him had haunted her for fourteen years.

And Sanji was new. Most everyone was new. And it was hard, far more difficult than she'd expected, to let down her guard.

Zoro looked at her incredulously for a moment, understanding now why she'd acted so oddly a moment ago. Maybe she was free, but surely her mind wasn't. He remembered, after all, his mistrust in Robin when he'd first met her, how he'd acted towards Sanji earlier about Ace.

He understood.

But he'd also decided to believe in Sanji.

The blond glanced back over his shoulder innocently to check if they were following, and he met Zoro's eye, his expression instantly changing the second he saw something was amiss.

Sanji stopped, looked unsure of what to do.

Zoro thought about his smile, how hopeful and bright it was. And he thought of his promise, how he'd reacted to the news of his brothers' return. He thought of how his own heart raced and his head spun more and more the longer they were together. He thought of how, until he'd met Sanji just a few short days ago, he'd never felt that way….

Zoro shifted a serious gaze back to Kuina.

" _Yes,"_ he answered. _"We can trust him."_

Kuina looked at him, worry in her eyes and maybe a flash of subconscious hurt that Zoro _would_ trust a new human so readily.

But with his jaw set, his voice steady and strong...she had no choice but to trust in _his_ word.

" _Okay…"_ she replied, her hand falling away from his arm, a heavy shadow replacing it, blocking the sunlight shimmering down from above.

Neither noticed for a moment, Zoro even nodding and shifting his gaze back towards Sanji, but it was the blond who had his neck craned, looking towards the water's surface high above, at a long dark shape moving along slowly….and the M.A.R.I.N.E.S. logo emblazoned on the hull.

* * *

 _ **East Blue Naval Base**_

* * *

The commotion from the pool was loud behind Ace, the cabin simulation box whirring and clicking as the huge robotic arms slowly tilted and lowered it into the water.

Ace, along with several others, were supervising the training, teaching new recruits emergency procedures for how to survive a sinking ship.

Or rather, he was _supposed_ to be supervising. But with Thatch and Vista doing the teaching, Namur and Izo in the water making sure no one drowned, and Jozu manning the crane, that left him and Marco without much to do apart from surveying the perimeter of the huge pool.

Thus, Ace found his attention wandering, despite the excitement in the pool, his mind entirely preoccupied with Whitebeard's ship currently visible sailing away on the sea out the tall windows, heading north towards the horizon, the sun nearly blinding off its white form.

The whistles and shouts of commands from his comrades echoed in the cavernous room, along with the sound of water splashing and the gasps of the recruits as, one by one, they escaped the simulation and surfaced again.

But Ace's thoughts were with Sanji, wondering if he'd made the right decision telling Whitebeard about his plight, if any of this would help matters.

Whitebeard had agreed to act secretively for now, only informing a trusted few, until he learned more of the situation, for which Ace was grateful. But he'd also insisted Ace stay behind, as he'd apparently be "too emotionally invested" to be of much objective help.

Sanji hadn't answered or even read his texts, the later ones turning into apologies the longer Sanji didn't respond.

Was he out there in the sea? Was that why he hadn't replied? Was he angry? Or worse, in danger…?

Ace had no idea, but not knowing was making his heart pound in his chest, his stomach twisting itself into knots the farther that ship got from port.

He wanted to follow, but to do what? Go to the M.A.R.I.N.E.S. too? Check B.A.R.A.T.I.E. for Sanji? He didn't know. But he wanted to fucking _do_ something already, not stay here _wondering_ about the safety of his best friend.

He heard a pair of sandals come up beside him, squelching lightly in the puddles strewn across the wet poolside.

His eyes didn't leave the ship, but he knew it was Marco. He could smell the faint scent of his pineapple shampoo, enhanced by his damp hair.

Marco now knew about Sanji. He'd been asked by Whitebeard to accompany him to M.A.R.I.N.E.S. HQ, but the man had elected to stay behind to keep an eye on Ace.

He said nothing for a long minute, standing just as Ace did, both of them in their casual training uniforms - swim shorts and a white T-shirt - but stances as rigid and formal as if they'd been fully decorated, hands clasped behind their backs as they watched the ship in the distance.

The recruits had pushed out of the pool now, all sitting on the side within earshot, relieved laughs and claps on the back following their successful simulation.

Marco finally lowered his voice, speaking so only Ace heard.

"If there's no word from them in a few hours, I'll go with you. Thatch said he would too."

Ace didn't reply, though a huff of both surprise and relief wanted to escape him.

He stood there, then subtly turned his head to glance at Thatch by the pool, who was already looking at him, his friend and fellow commander meeting his eye from over his clipboard.

Thatch's lips turned up knowingly and he nodded silently.

Out of the corner of his eye, Ace saw Marco's grin when he turned back to the window.

Slowly, a rebellious smirk pulled across his face.

* * *

"What are you doing?!" Zoro screeched after Sanji in a rare bout of fluency as the blond flicked his tail and started up towards the surface, going after that slow-moving boat.

"Going to talk to them!" Sanji shot back over his shoulder, with no signs of slowing down. "This is what I wanted to talk with you about! But it looks like the party came to us."

Zoro left Kuina's side to catch the end of his tail, give a yank, and he used the momentum to swim up himself, hands reaching Sanji's arms.

"Going with you," he insisted, the blond looking disgruntled from the backwards tug, and he pressed his own palms to Zoro's chest, pushing him away gently.

"No, Zoro, just-" he started to say. "Look, I want your help, but just wait a minute, okay? Lemme see how they react first."

"Bad idea," Zoro implored through gritted teeth, but Sanji gave a small smile, lifted hands to the mosshead's cheeks where thumbs brushed soothingly.

"We don't even know who's onboard," Sanji assured, giving one last stroke before he made to pull away.

But Zoro's worry was too great. He yanked Sanji back again and slammed lips into his, stifling a surprised noise in Sanji's throat before he felt long fingers slide into his hair, the other merman's lips moving against his to kiss him slowly.

A minute, and they broke apart, Sanji's lips slowly parting from his, his hands sliding over Zoro's jaw. Zoro kept his eyes closed as those hands fell away, and he felt Sanji's lips press to his forehead a second later.

He opened them to see the blond smirk at him, give a pat to his cheek. Then those blue eyes looked away and with another pump of his tail, Sanji glided up towards the surface.

"Watch my back," he said before finally swimming off.

Zoro watched him go for a moment, concern still simmering in his gut, but letting himself slowly sink back down to Kuina's side.

It wasn't until he felt the heavy weight of his friend's stare that he finally glanced over at her again.

Kuina was glaring at him, a look of complete disbelief and shock on her face.

For a moment, Zoro didn't understand…..until he realized he'd just exchanged a rather intimate display with Sanji without thinking about it. It was embarrassing enough that he rolled his eyes to cover it up.

Until she blurted out, "Is _that_ why you trust him?"

Her tone was incredulous, almost a little hurt, but Zoro couldn't think about that now.

Instead, he narrowed his eyes and ordered, " _Kuina, go back to Noah."_ There was no way he was letting her stick around while potential danger lurked nearby.

But she ignored him, persistent, even when he moved towards her, placed hands on her shoulders and physically tried to steer her away.

"Please tell me you _actually_ trust him, and not just because you're blinded by-"

 _"Kuina. Go back to Noah,"_ he insisted more adamantly, not even understanding her full argument.

Frustrated, she growled, clearly torn between the desire to flee, to never deal with the M.A.R.I.N.E.S. again, and the need to stay with Zoro, to put her own safety at risk in order to ensure his.

"But - Zoro, you-" she stammered, unsure how to even make sense of the possessive anger that had flared within her when she saw the two embrace. Maybe she should have assumed Zoro would have moved on with his life, but it still fucking _hurt_ when she'd had no such opportunity. Zoro, and the memory of their friendship, was all she'd had.

But it wasn't all Zoro had.

" _I'll be fine,"_ he said. _"He has a bracelet. I've been human before. It's no big deal, and-"_

"What?!" she yelped. "What the fuck do you mean?!"

Suddenly, this wasn't just about Zoro's relationship with Sanji. Suddenly, this was Zoro willingly embracing humans, her captors, the ones who had stolen her life and nearly taken his. Suddenly, she felt betrayed, despite knowing nothing about the situation, thinking of her friend walking on land with humans, living a double life.

Fuck, it stung more than it should, and then there was the image of Zoro, a human in a M.A.R.I.N.E.S. uniform, sneering at her through a wall of glass.

Her eyes were wide and she flinched hard when Zoro's hands gave her shoulders a shake, the merman unconscious of his strength.

" _Kuina!"_ he hissed. " _Come on! Get a grip! I don't want you to-!"_

Just then, there was a great muffled splash from far above them, enough to send a school of fish darting away and scattering quickly.

Immediately, both Zoro and Kuina craned their necks towards where the boat had passed overhead, now a short distance away.

And sinking deep into the water was a sturdy net, closing its tangled grip around _Sanji_.

Both their minds sank immediately back into that final memory they had of each other. The nets, the searing heat of the sun on the deck of the ship, the thrashes and screams….

" _Shit!"_ Zoro cursed, and he let go of Kuina to speed towards it without another thought, ignoring her panicked cries of, "Zoro! Zoro, no! Don't-!"

He pushed himself harder to close the distance between him and Sanji before that net breached the surface, and he managed to reach it in a flurry of bubbles as his hands clamped down onto the thick rope.

He stopped seeing straight, only aware that he'd let loose a ferocious growl, and razor sharp teeth instantly bit down to gnaw on the closest rope in a struggle to break it.

His head thrashed ferociously, even as the net pulled him along, and then there were fingers in his hair, sliding down to grip his wrists.

Sanji's voice came through to him, the blond's fingers now daring to venture down to his jaw, gently trying to pry him off the net.

"Zoro! Zoro, let go! Zoro! Come on, idiot! What are you doing?"  
Zoro finally broke away, but only to glare at him, teeth still bared.

"It's no use!" Sanji continued once he had his attention. "They're only gonna pull it up anywa-!"

"Shut up!" Zoro barked harshly in his panic.

Still, he looked up, where the quivering image of the boat grew closer by the second, a long crane extending out from it, supporting the net. There was no time. They were too close to the surface.

With a frustrated sound, his eyes flicked back to Sanji, who was watching him with surprising calm given the situation.

"Let go," said the blond, eyes on Zoro the whole time, and it felt less like an order than a test, to see if Zoro would actually do it.

The merman wasn't sure what the answer Sanji wanted was, but he knew one thing for sure. He wasn't letting the blond go. Not without him at least.

"Going with you!" Zoro growled again, and as soon as he'd said it, Sanji actually smirked a bit.

And he didn't protest. In fact, he gestured for Zoro to get a firmer grip on the netting, which he did, hoisting himself up and slipping arms through the gaps, arms holding onto Sanji's waist much as they had that morning at the docks.

Sanji stuck his own arms through so he could wrap them more securely around Zoro's shoulders, in hopes that, when they finally broke the surface in a few mere seconds, Zoro wouldn't fall back in.

From the seafloor, Kuina watched in horror as Zoro actually _latched on_ to the net, allowed himself to be pulled up along with Sanji. Her heart beat rapidly in her chest, the panic combining with the anger and stupid betrayal she still felt, all of it working to immobilize her.

Despite the countless times she'd envisioned herself changing the outcome of her capture, rescuing both herself and Zoro from those nets, she couldn't move. Because she knew what awaited her above the surface. Glass cases. Needles. Loneliness, pain, and confusion.

And she was terrified.

She'd finally crawled her way out of that horrible life, and she didn't want to fall back down, knowing what that meant.

But Zoro…

Wide eyes shifted first to the knives clipped on her backpack, then to the long blade of the sword lying atop the rock nearby.

Her fingers twisted around the bracelet she still held in her trembling hand….

 _TBC..._


	11. Reeling

The thick ropes scraped roughly against Sanji's skin as the net broke the surface with a splash, exposing them to the searing heat of the sun and the whipping of the wind over the waves. He felt Zoro's weight grow heavier, the merman's grip tightening almost painfully around his waist, gravity taking effect.

Sanji grappled to hold onto him, stop him from toppling the far distance to the water below, the net shooting up nearly twenty feet now above the waves, lifted by the ship's crane.

And then Sanji realized he couldn't breathe.

His eyes went wide, a choked sound escaping his throat, the horrible sensation of his gills closing up driving him into debilitating panic.

There was the instinct to gasp, as he would if he were human, but nothing happened when he opened his mouth and tried to draw in breath. His chest merely twitched fruitlessly, and his mind burst with blinding fear.

Gills burned like fire, eyes watered. His heart threatened to beat right out of him-

"Brace - let-" came Zoro's strained voice.

Then the two of them hit a hot white deck, tumbling roughly together as they collapsed, and Sanji remembered, a flash image in his mind of the one thing that could save him.

He finally managed to lift his hand from Zoro's shoulders and press the button on that bracelet, the metal ring popping off his wrist into his palm.

His eyes had shut at some point, but a warm, creeping sensation instantly crawled up his tail, leaving two legs in its place. And then, a great gasp when the warmth reached his chest, the blond finally taking in gulp after gulp of sweet air.

Moving was impossible for a long moment in his relief, lying there flat on his back, his wetsuit shorts soaking, still tangled in net, but it didn't matter because he could finally-

A feral snarl to his right, and his eyes snapped open to the deep blue sky above, and the sounds of a wet tail slapping the deck repeatedly as it thrashed. He knew the sound well.

Only now, it was associated with someone he was beginning to care for.

Shit.

Sanji shot up, arms flailing to free himself from the net.

He'd barely managed to pop his head out before two pairs of hands grabbed him roughly by the arms, yanking him from the net and dragging him backwards away from where he now saw Zoro struggling against two other men.

"Let me put it on him!" Sanji cried, still clutching the bracelet tightly in his fist. He didn't explain what "it" was, but there was no way they didn't know, especially after he'd just transformed himself in front of their eyes.

Panic left his voice shrill and gave his racing heart no rest, but dammit, Zoro's fight was slowing, the merman's thrashes more spasms than anything as his body began to give out, helpless to escape.

Sanji tugged, lashed out with a kick to one of his own captor's shins that drew a satisfying yelp of pain.

"Let me - fucking put it on him! Please!" he cried again, desperate, eyes not leaving Zoro, whose form grew limper by the second.

That was when Sanji finally felt those grips on his arms loosen, and he rushed across the deck, bare knees slamming to the floor beside Zoro, the merman's torso flopping unceremoniously to the deck when the men dropped him, a glazed look beginning to come over his dark eyes.

He took hold of the merman's wrist, clamped the bracelet on hastily, and then his hands were at Zoro's face as he transformed, his head dropping in relief when the merman finally took a gasping breath and began to cough, fully human again.

"It's okay. It's okay, breathe," Sanji murmured, stroking at his jaw until Zoro shifted, flopping over onto his back tiredly, panting.

Only when he was satisfied Zoro would be fine did Sanji turn to the group surrounding them, still hovering protectively over the recovering merman, a hand on his chest.

"You _bastards!_ You could've killed him!" he growled, trying in vain to squash the very grave and very shocking realization that he was truly dealing with people who disregarded life so easily.

No one replied, and, in fact, the roughly twenty people lining the wide deck resembled soldiers more than scientists, all dressed uniformly in white, the blue M.A.R.I.N.E.S. logo visible on their chests. Their white caps shielded eyes, but did nothing to hide the coldness behind their stares. A chill ran down Sanji's spine, despite the heat of the day.

This was Sanji's first real look at his surroundings, a huge research vessel that was bigger than anything B.A.R.A.T.I.E. owned. The deck was clean, clinical almost, and above them the ship's interior rose two stories, the crane that had carried the net now swinging back into place atop the highest level.

The sound of a heavy metal door unlatching, and Sanji's eyes darted to the second story balcony, where a broad man, clad in a colorful floral shirt, stepped out into the sunlight, arms, thick with corded muscle, gripping the railing.

His gaze was stern beneath his M.A.R.I.N.E.S. cap, and his teeth bore in a near snarl around the cigar that puffed smoke around his head. If his crew were soldiers, this man looked every bit an unforgiving admiral, not even the brightness of his shirt able to soften his features.

He pulled his cigar from his mouth and blew out a stream of smoke, a flick of his finger sending ash flitting away in the wind.

"Sanji Red," the man rumbled down at them, voice low and deep, dangerous. "I've been waiting a long time to meet you."

Beside the blond, Zoro finally sat up, his slowing breaths laced with a subtle, threatening growl.

Sanji didn't have to look at the merman to feel the hatred in Zoro's glare.

And he also didn't have to know anything about the man standing above them to feel that hatred himself.

After all, this was the man who'd killed his mother.

* * *

Kuina's eyes remained fixed on the stationary hull of the ship high above her that served as a dark cloud blotting out the sunlight, sheets of bubbles still raining down from where the net had breached the surface a minute before.

She stared at that ship, waiting, _hoping_ to see the net come crashing back down, for Zoro to get the hell out like he _should have_. Did the idiot have no sense of self-preservation? And though she knew Sanji had a bracelet, it did nothing to quell the fear that she'd just sat idly and watched Zoro disappear again, possibly forever.

She waited, brow furrowed tight and her heart thumping, a strong beat in her taut chest.

They weren't coming back, and dammit, why? Why would Zoro risk everything for a _human_ , regardless of his blood? What had changed so much in the years they'd been apart?

She knew what awaited the two if they didn't escape. She knew the pain and danger that followed, and while Zoro was strong...

But no. Wouldn't it be insulting to assume Zoro would fall prey to the same weakness and compliance she had? Did she really believe _Zoro_ was capable of giving up? He'd apologized for doing so, but looking at him now…. He'd grown so much.

Still, her own trauma continued to drift into her mind, a cloud over the confidence that had shone on her only minutes before, finally swimming free in the place that had been her home so many years ago.

Could she do it? Could she face her prison again, even when she held the key to literal change in her hand, fingers still twisting anxiously on her own bracelet?

"Kuina!"

A sudden voice cutting through the water had the mermaid jolt in surprise, just before a hand clamped down on her arm, bringing her face to face with the Queen herself, the mermaid's momentum pushing them sideways in the water.

It took a beat for her to process not only the Queen's arrival, but also the fact that she was this far out in the rock field. It had been so long, but still, Kuina didn't think she could remember a time she'd seen the Queen venture this far from Noah, cautious as she was.

There was no time to linger on this surprising fact, however, her own panic over the situation conspiring above quickly returning when she met the wide blue of the Queen's eyes.

"Your Highness! Fuck-! Your Highness, Zoro was-!" Kuina stammered, vaguely registering the appearance of the three brothers, now swimming far more casually up behind their sister as if their former captors' ship wasn't still lurking above.

"We have to get away from here," the Queen interrupted, suitably concerned at least, stealing nervous glances above them, hand giving an insistent pull on Kuina's arm.

As if Kuina didn't know that, but somehow, despite the risks, she couldn't bring herself to abandon her post.

"But Zoro and Prince Sanji were - the M.A.R.I.N.E.S. took them!" she insisted, a hand coming up to grasp the Queen's wrist in hopes of loosening her grip. "I tried to - tried to stop Zoro from going to the surface, but-!"

Eyes darted to the three brothers, and she wasn't sure if it was relief or surprise that passed through her when she saw their eyes widen, the glances of shock they exchanged.

"Shit, he actually had the balls," said Niji, eyebrows giving an impressed twitch over sunglasses, his lips curling up to reveal a sharp-toothed grin that was less proud than it was sadistically gleeful.

Kuina stared at him for a moment, baffled at his tone, and further perturbed by the ever-persistent tug on her arm urging her to swim _away_ , to leave. Even Ichiji, normally the most decisive of the three, floated solemnly with no move to act.

"Why the _fuck_ aren't you guys doing anything?" Kuina cried. "That's your brother up there, you know! Are you three really going to let your stupid grudge stop you from-?"

"He thinks he can change things with them. He told us not to follow him," Ichiji cut in seriously, the redhead crossing arms tightly over his chest, tail giving an agitated flick. "And why the hell would we? We just left that place."

"We're takin' bets on whether he makes it out or not," Niji cut in with a dark snicker.

Kuina scoffed, instead rounding on Reiju.

"And what about Zoro?"

"I advised they go together," the Queen replied, though her voice had become far less assertive, and her grip far more tentative on Kuina's arm.

Despite the mermaid's uncertainty, Kuina let out an unabashed noise of frustration.

"You _advised_ this?" she pressed.

It was Yonji who spoke up next, for the first time since their arrival, arms also crossed over his chest to mirror his brother, though he was hunched forward nervously, and his eyes didn't leave the hull of the ship.

"They were just going to negotiate," he muttered sulkily, and Kuina frowned, noticing a slight tremor run through the merman's shoulders. Suddenly, his sulky tone looked a lot like fear, a far cry from his normal bravado.

Her eyes automatically drifted to Yonji's scarred cheeks, a reminder of long nights full of fruitless pounding upon glass and frustrated screams…twirling wisps of blood in the water.

"I don't think a _net_ swallowing them up is a good negotiating tool," she eventually shot back, though her voice had quieted some in the face of the merman's nerves.

There had to be a way. There had to be a way to earn their support. She didn't know what she was going to do, but if all they did was _wait_ , she feared it would be for something that would never come. She feared that it would be too late, and that _trust_ in the situation wouldn't be enough.

When had it ever been enough?

And it _wasn't_ enough, not when, suddenly, a shift in the currents swirled around them, forcing all of them to look up, dread spilling over as that dark cloud began to move. Massive propellers churned the water behind into frothy white tails, swishing their fins to push the ship forward, with two pieces of unintended cargo still aboard.

Kuina didn't hesitate.

She broke free of Reiju's grasp, lifting her fist to shove her bracelet roughly in the other mermaid's face.

A flash of shock passed over the Queen upon noticing it, and her expression morphed through confusion before landing briefly on poorly-hidden fear before Kuina clarified.

"It's not your brother's," she assured. "He still has his. It's from HQ, the one I used to help us escape. I have it, and I'm going to do something."

"Kuina, _no_. You just _escaped,"_ Reiju insisted, quick to protest, that same fear and perhaps a twinge of unbecoming panic shattering her regal countenance. "Like hell I would let you-"

"You don't know what it's like there," Kuina argued, speaking quickly now because that trail of bubbles on the surface was growing longer, the ship moving away ever farther. "You don't know what Sakazuki is like, what he did to us. Your brothers might try and act strong, but that place fucked them up too."

"Then it would be foolish to-!" Reiju pressed, only to be interrupted once more.

"Sakazuki does not _negotiate_ ," hissed Kuina. "He will not listen to him-he doesn't care! And you have no idea _how badly_ he's wanted Sanji."

"All the more reason for you to stay put!"

Reiju's voice rose, assertive again, and her grip was back on Kuina's arm, even as her gaze flicked indecisively towards the retreating ship.

In that moment, Kuina didn't see their strong Queen, but rather her own self. Herself as she'd been for all those years, lonely, afraid of losing what little she had left, willing to place hope in foolish things if it served as an excuse for her own passivity, her own instincts for self-preservation.

This had never been a version of herself she'd been proud of, and it was one she didn't want for the Queen either, who she knew deserved none of the pain she'd been dealt in life, surely.

From a young age, Kuina had wanted to protect. And protecting required action.

"I _can't_ ," Kuina countered, this time reaching out to take hold of the Queen's shoulders, hoping to feed some form of strength, if only through her tone, her touch. "That would be—pathetic, I-"

She paused, closed her eyes briefly, then started again, feeling the burning stares of the three brothers now fixed on her as well.

"Your Highness, for so long. For so long, I have _wished_ I could change my past—wished I could _do_ _something_ , and I never did because I was scared and I thought there was nothing left fighting for."

A beat, and then a tiny smile tugged at her lips because she saw it, the small flicker of recognition in the Queen's eyes. The pair were looking into a two-way mirror now, she knew.

"But it's not true - it can't be true!" she continued, giving the mermaid's shoulders a gentle shake. "I'm still fucking scared, but being back here and seeing - all I was missing, what _you_ were missing... I - I have to go. If there's any hope of changing things, I have to go."

There was silence, during which Reiju's eyes stayed on Kuina's face, even when Niji's voice piped up stubbornly.

"You're crazy if you think we're coming with you!" he cried, but Kuina was quick to whirl on him.

"Did I ask you to?" she snapped. "No, I'm going alone." And while that thought was a little disheartening, she knew the brothers, brash as they were, were right about one thing.

They could not risk their newfound freedom so carelessly.

As if to confirm this, Ichiji's low tone rumbled from behind Reiju, and though it was serious, his voice lacked the defiance of before. It was quiet, almost tired.

"After all this," he said. "You're really going back."

Kuina's hands fell from Reiju's shoulders, and she turned to level the redhead.

"I didn't escape so that someone else could take our place," she stated simply. "Not even a human."

Ichiji's jaw merely clenched in response, a subtle twitch, but one Kuina recognized. It was a signifier of rare inner turmoil, and she could count on one hand the number of times she'd seen it. For once, it was hard to predict his reaction.

With Yonji still hunched uncomfortably, and Niji grinding teeth, there was no one left to speak. Save for Reiju, and what she said surprised them all.

"I can….alert Dr. Red," she said, her eyes clear and her voice beginning to regain some of its familiar certainty. "O.H.A.R.A. is too long of a swim, but B.A.R.A.T.I.E….. Dr. Red can call Dr. Nico at least."

"More humans?!" Niji growled in shock, but Reiju was quick to glare at him.

"Shut up!" she hissed right back at her brother, her hair a rosy cyclone around her head, and surprisingly, Niji obeyed, instantly snapping his jaw shut, brows furrowing deeply, but he remained silent.

Reiju's plan was unclear to Kuina. She could vaguely recall such names, _human_ names, but it was difficult to piece together their correlation, not to mention how the hell _any_ of them were going to help.

But Reiju's gaze burned with growing conviction when she met Kuina's once more, their reflections now balanced without a semblance of glass to separate them. Kuina knew she could never let glass confine her again.

There was no time, so she was left with only one question.

"Do you really trust them…?"

Reiju's reply was immediate, even in the face of that question's weight.

"With my life," she stated seriously. "And with yours."

Kuina closed her eyes, actively squelching the nerves and mistrust that bubbled within her. They needed the help. _Zoro_ needed the help. And though she hardly knew the merman he'd grown to be….if _he_ could trust humans after everything. If the Queen could….

She opened her eyes and reached out to grasp the ivory hilt of that brilliant sword, still resting atop the nearby rock. The hilt nestled well in her palm, and she chose strength over fear.

"Then there's no time to waste," she said, and with a flick of her tail, she made to rush after that boat, shrinking into the distance.

She didn't make it far before Reiju swam up too to block her path, lithe hands coming to her arms again, but this time, not to stop her. They were there as a form of support, surely.

"Kuina," she murmured softly, with a fiery gaze, but a gentle touch. "Bring them back. I can't do it again. I need…all of you."

Kuina understood. That was _why_ she was risking this. Things needed to change.

"We're not alone this time," she replied. "None of us are."

A final look at the four siblings, who she _would_ protect. She wouldn't let any of their own be taken. Never again.

Then she was off, darting as fast as her tail would take her through the open water, in the direction her migration instincts falsely labeled as "home."

Reiju watched her friend disappear yet again, hands lifting to hold herself lightly, her eyes fixed on Kuina's ashy tail, but her mind remembering one of deep blue, a gleam of golden hair instead, that had vanished with a reassuring smile and never returned.

Until Sanji had….

She turned abruptly, in the opposite direction of Noah, towards the land, miles away.

"Do as you wish," Reiju muttered to the three mermen still floating, dumbstruck, in the water behind her. "But I truly meant it. I need _all_ of you."

Then she too was off, without so much as a meeting of eyes.

The brothers were left alone in heavy silence.

* * *

The air was quiet, save for the heavy thud of footsteps descending the metal stairs from the upper deck, as if Sakazuki wore boots, not sandals.

Quickly, Sanji scrambled to his feet, shaky after spending hours with a tail, but he managed, automatically turning to help Zoro, who nearly yanked him right back to the deck with his imbalanced insistence.

By the time Sakazuki reached the bottom of the stairs, Sanji had moved in front of Zoro, a hand reaching back to hold onto the merman's wrist protectively. No way in hell was anyone getting near that fucking bracelet.

Sanji had never been afraid of another human being before, not truly. That was surely a sign of privilege in his life, and though he'd come with such conviction and _fury_ , he still felt panic creeping on the edge of his consciousness. The man was simply approaching, and calmly at that, but Sanji still felt his grip on Zoro tightening, right along with his chest, breaths coming lighter beyond his control.

But he stood his ground, particularly when he felt Zoro's fingers lacing with his. There were risks involved with giving away just how much Zoro meant, but Sanji needed the anchor.

Sakazuki was tall, taller than Sanji, and deep-set eyes were well shaded by heavy brows, unreadable caverns.

He stopped a few paces away and pulled the cigar from his mouth to flick off some ash before he spoke.

"You've made my job far easier than expected, Mr. Red," he drawled casually, as if they weren't speaking of potential kidnapping. "Practically climbing into my net as you did. And I see you've brought a friend."

Instinctively, Sanji's lips pulled back in a warning snarl much akin to the surprisingly aggressive energy he'd felt the first time he'd transformed.

"I wasn't aware your _job_ was to hold living beings _prisoner_ -" he spat out, anger rising within him, only to be cut off by Sakazuki, the man's voice still level.

"And the fact that you're aware of this situation at all means that I have every right to get acquainted with you," he said slowly, a hint of annoyance in his tone that might soon have morphed into something dangerous.

Sakazuki watched him for a long moment, the man's gaze one of mere boredom that still somehow managed to send the cold grip of fear clenching harder in Sanji's gut. But this time, not for his own safety.

No, his thoughts immediately wrenched to his father. His infuriating father who'd kept this whole damn secret from him for his entire life. His stubborn father who'd had nothing but his best interest in mind, who'd done nothing but _protect_ him, even if it meant concealing the truth, and dammit, now was _not_ the time to feel guilty over their argument from the previous evening. Now was _not_ the time to wonder if he should have been more understanding, more cautious.

It was the wrong time to imagine his father's stern gaze in place of Sakazuki's. The wrong time to wish he was here to help deal with this shit…

But now was also not the time for inaction. Not anymore. And Sanji knew he couldn't afford to let his resolve waver.

And so, when Sakazuki abruptly turned on his heel to head back across the deck towards the ship's interior, frustration immediately swelled in Sanji's mind.

"Let's head back," Sakazuki announced, with a nonchalant wave of a hand that sent several of his crew members scrambling to their posts once more. "He'll do for now."

"But sir, what about the-?" cut in one crewman, his voice hushed as he flicked eyes to Sanji and Zoro.

"As I said, he'll do for now," replied the captain. "And something tells me he will come quite willingly if it means we will refrain from any further searching."

His hand met the railing of the steps, just as the ship gave a slow lurch forward.

And the moment the man started to ascend, the moment the ship began moving again, Sanji felt his feet move before he could stop them, felt rage bubble within him that he _should_ have felt years ago. The merpeople's rage, surely.

Zoro tugged his arm back, but still Sanji pulled forward towards the indifferent man who'd wrought _so_ much pain, but now did so little in the face of the justice he should have answered to.

"You bastard, face me, dammit!" Sanji called after him, Zoro stepping up his side, a low growl escaping him, seemingly fueled by Sanji's outburst.

Sanji didn't know what more he'd planned to say, but there had to be _something_. He couldn't let this man walk off, like he'd done nothing wrong and owed no explanation. He _needed_ one, and it was just as infuriating to see the heavy sigh, the slow way the man turned around, almost devoid of energy when Sanji felt it coursing through his entire body in waves with every thundering beat of his heart.

This was for his parents, his siblings. This was for the scars on Yonji's face and the pain behind Niji's scowl. This was for the tired mistrust he'd seen in Ichiji's eyes. This was for the way Reiju held herself, as if she was the only one in the world who would.

And this was for Zoro, for the ferocious hope he held in his gaze, his kiss, and for the fact that he now stood beside him with just as much ferocity, just as much strength of will.

These thoughts whipped around Sanji's mind, a cyclical mantra that only grew louder as Sakazuki silently crossed the deck to him again, popping his cigar back in his mouth, and began his own slow circle around the two, a watchful vulture under the blazing sun.

"Human," he eventually mused, stopping before Sanji once more, though he spoke the word as an insult. "Entirely human, are you not? You stand; you breathe. You fooled even yourself into thinking so….. And yet, this…"

Dark eyes flicked clearly to Zoro's wrist and the metal bracelet encircling it.

The instant the man's fingers so much as twitched towards it, Sanji jolted, clamping both hands over that bracelet with a fierce protectiveness.

" _Don't_ touch him!" he snarled, and though he felt Zoro's eyes fall on him, he didn't look, fury filling his chest, as white as the ship's bright deck. And then his next question burst from his lips without further meditation.

"Why?" Sanji gritted out, and when he didn't receive an immediate response, his tone became more demanding. " _Why!_ You _owe_ me the answer! _Why_ have you done this!"

Surely the answer didn't matter. The answer couldn't excuse what had been done, what had been _lost_.

No remorse crossed Sakazuki's face, and in fact, how his eyes narrowed seemed almost condescending, and Sanji despised the feeling it wrought, like he was a naïve child whose tantrum was about to be discredited.

Still, he waited, breaths struggling to remain measured, aware of Zoro's less controlled ones close to his ear.

By the time Sakazuki finally opened his mouth to speak, the blond felt nearly ready to explode with tension.

"Because your value is greater than a mere human's, Mr. Red," Sakazuki said slowly around his cigar, his words as thick and negative as the smoke that hung around his head. "The same goes for all of your kind. Do you not realize what your father unlocked?"

He paused to jerk his head towards Zoro's concealed wrist.

"That bracelet could hold the key to eradicating every single malady, every single disease on the planet, given time. Your kind, your ability to transform, could save millions - _billions_ \- of lives, if studied. As a fellow scientist, I'd assumed you were keenly aware of this-"

"So you _murder_ sentient beings?" Sanji interrupted. "Hold them against their will? You-"

"I _protected_ them, Mr. Red, and you would be foolish to think otherwise," Sakazuki growled right back, threatening irritation returning to his voice, the flowers on his shirt beginning to look more like twisting flames.

"If I had not acted quietly," he continued. "An all-out war between your kind and ours would have quickly alerted the rest of the world. And the Government would have surely bore down upon your tails with far more ferocity than I ever have. Have I not left you in peace for fifteen years?"

Sanji's hard gaze never lowered, but he didn't reply to the question, refusing to accept that, even for an instant, those words had made sense. He wouldn't acknowledge it, couldn't, not when the price of that peace had been so steep.

Sakazuki didn't wait for a response, and his voice quieted once more, losing its edge. To unsuspecting ears, it might have even sounded gentle.

"Thankfully, the Government has been too preoccupied with….other matters in recent years, allowing me to research without restrictions. But they've wreaked havoc before, and _your_ kind would have been next had they discovered the truth.

The sacrifice of a few can save _far_ more. The man you now call 'Father' understands this concept. Or rather he did. Now it seems he has no trouble sacrificing you as well. I suppose the ultimate example was your mother-"

"Don't even _talk_ about her!"

The words erupted from his mouth before Sanji could stop them, and he felt no surprise, defending someone he'd never thought to defend until a few days ago. His mother had given him _everything_ , and he hadn't even known.

He heard another primal snarl leave Zoro, ever sensitive to his upset, so he forced himself to stay rational, however unnatural that felt in that heated moment.

If he had any hope of negotiation while he had the bastard talking, he couldn't afford to lose it completely. Not yet at least.

He took a deep breath, slid fingers over Zoro's skin to ground himself.

"I'm not an idiot," Sanji said bitterly. "I know what the bracelet could do for the world. So take the bracelet, but not unwilling _lives._ What were you even planning to do, if not exploit them? Pass it off like you made them yourself?"

Sakazuki's lip curled subtly for a moment, though his mouth quickly straightened itself back into an impassive line.

"…If you joined our cause," he replied. "We could share the benefits. After all, you are one of your birth father's creations, aren't you? Wouldn't you like to honor his legacy?"

Insulted, Sanji scoffed.

"I won't honor it by becoming your experiment."

"But you are so willing to take up this mantle of 'protector,'" came Sakazuki's retort. "Just like your parents. Your compliance would not go uncompensated. The secret of your kind would remain safe. And we would have no need to take any other specimens. All thanks to you."

To Sanji's surprise, Zoro's voice sounded low in his ear, in direct response to the man's speech.

"Don't - listen," he hissed, leaving Sanji to wonder how much the mosshead had actually retained of what was being said.

The blond's hand lifted to the merman's chest, pressing there below his black beads with reassurance, eyes not leaving Sakazuki.

Of course, Zoro was right. For once, he would give him that.

"If I submit to you," he finally said, considering his words carefully. "My parents' sacrifice will be for nothing."

And it was a bit of a shock, even to himself, when he found his tone changing.

"If research is what you wish to do, B.A.R.A.T.I.E. can help you," Sanji pressed with earnest candor. "O.H.A.R.A. can help you. Hell, the merpeople can help you! We can do this together without any casualties. Without any more pain and suffering!"

Why? Why was he even offering that? Did he think it was deserved?

No. Surely not.

But did he think that maybe, somehow, it was what his parents would have wanted…?

He found himself leveled by Sakazuki's gaze once more, the judgment and calculation ever present, though, for a split second, Sanji thought he detected something else. Something far away, in another time and place.

Finally, Sakazuki sighed.

"Perhaps you are right, Mr. Red," he replied. "Then I will simply invite you. I will invite you to observe my findings, my developments. And let you decide for yourself what is worth fighting for in the end."

Again, Zoro growled, almost unconscious of it now, and Sanji slid his fingers down over the fist the merman had tightly clenched.

"Look at that," said the blond sarcastically, a brow twitching up. "You _can_ negotiate like a human."

Sakazuki's eyes traveled over Sanji's form before they met the blond's once more.

"There's only one human between the two of us, Mr. Red," he stated.

He left that assertion hanging for a long moment, not even the wind that now whipped across the deck with the ship's movement enough to sweep it away.

Then he turned once again, retreating.

"We should arrive within an hour," the man added over his shoulder. "Should you and your friend choose to leave before then, this boat will make a return trip to East Blue. And I'm sure all of your kind will know why."

Sanji's heart beat fast, watching him go, feeling the sting of resentment hooking his heart.

For the first time in his life, Sanji thought he understood how it felt to be bait.

* * *

 _ **East Blue**_

* * *

"Captain Smoker….Sir…."

Gloved hands tightened on the ship's silver wheel, and the captain turned to see Tashigi entering the small wheelhouse, barely catching herself on the doorframe when the boat popped a little too high over a wave.

He reached over to crack open another window, allowing a bit more smoke to filter from the room, pluming out from the pair of cigars clamped between his teeth.

A grunt of acknowledgment, and he turned back to fix eyes on the shimmering ocean before them once more.

Tashigi said nothing right away, merely approached his side where she stood silently for a moment, though her very presence filled the room with a nervous energy. He waited for her to speak, as she was quite obviously working up to it.

The woman's thoughts practically whirred as loudly as the boat's engine in the silence, until finally, she seemed to settle on one question, accompanied with a huffed sigh.

"Sir, what are we going to do?" Tashigi asked, and he felt her apprehensive gaze on him.

If she was searching for a direct answer, she wasn't going to receive one.

Perhaps it was foolish, to come at this without a plan, beyond apprehending Sakazuki, but they were scientists, not pirates.

All Smoker knew was that there was a little green shape of another ship in their radar to the east, blipping far too close to the coordinates Robin Nico had given them. A ship with only ill intentions, surely.

A ship that needed to be stopped.

"Whatever needs to be done," he answered, knowing this at least was true. "It's time Sakazuki left the picture."

Tashigi's face blanched when he spared her a serious glance.

"You don't mean-!" she yelped, with a paranoid peek at Coby and Helmeppo, still out on deck. She quickly lowered her voice. "Sir, I agree, his methods of experimentation were horribly inhumane, but _murder?"_

At that, the captain merely smirked, removing his cigars from his mouth to blow out a stream of casual smoke, admittedly amused by her horror.

Until that amusement turned to alarm when, suddenly, Coby's voice, full of panic, sounded from outside.

"Tashigi! H-Hold on! Helmeppo, grab a life ring!" the young intern cried urgently, and the pair in the wheelhouse turned around just in time for Coby to stumble up to the door, glasses askew, pink hair tousled by the wind.

"Captain!" he shouted into the small space. "Man, er, woman overboar—"

But he stopped short, mouth quickly snapping shut before brows furrowed in absolute confusion upon laying eyes on the equally confused, but safe, woman standing within.

"W-Wait…Tashigi…?" Coby stuttered, and he quickly looked back over his shoulder at Helmeppo, already busy grunting out an irritable, "I can't believe this," as he tugged a large life ring off the outer wall of the wheelhouse.

And beyond that, in the water, sprouting periodically from the trail of white bubbles the vessel left in its wake, was a head of dark hair, struggling to keep up with their quick pace.

Immediately, Smoker and Tashigi shared a glance.

And then the captain hastily cut the boat's engine, turning the vessel hard to swing back towards the figure in the water, nearly sending both Coby and Helmeppo flying in to join it.

The boat slowed to a halt, bobbing idly until, surprisingly, a _sword_ of all things, glaring in the sunlight, clanged onto the back platform, followed by a pair of arms.

"Permission to board, Captain," Kuina said, not waiting for an answer from the stunned humans on deck as she snapped her bracelet onto her wrist and pushed herself up out of the water.

* * *

 _ **East Blue - En route to M.A.R.I.N.E.S. Headquarters**_

* * *

"Hey, babe?"

In response, Robin, gazing fixedly out the cabin window at the endless expanse of blue that had long since swallowed up the cragged coastline of O.H.A.R.A., pivoted to find her vision filled with the colorful pineapple print of Franky's open shirt. She lifted eyes to meet his.

Franky managed a slight tilt of lips in the face of her clear worry, a rarity on his girlfriend's ever-composed features, and he brought a large hand to the small of her back, coaxing her closer to his side so he could indicate the wide radar screen before them.

"'Nother ship just popped up in our radius. An' it looks like Smoker's changin' course…" he mumbled, tapping the form that had settled on the edge of their radar, heading in the direction of their own modest Sunny.

That now made five discernible shapes, their green silhouettes creeping like insects across the black screen, ever closer to what seemed to be a single destination. Two of them, the larger shapes of what were surely Admiral Whitebeard and the West Blue Navy's ships, were making a direct route to M.A.R.I.N.E.S. HQ.

Smoker's smaller vessel sat slightly off-course, towards the east, but now showed northward movement as well.

The fourth ship, closest to the north, was situated in what Robin recognized as dangerously close proximity to the merpeople's colony several dozen nautical miles away. They could only assume, with great concern, that it belonged to the M.A.R.I.N.E.S.

And now they had fair warning of yet another vessel approaching fast, its shape swiftly moving directly towards their research vessel, surprisingly.

"Better go and check it out. She's comin' up fast," Franky murmured, but Robin's only reply was a quiet, "Yes," her brow furrowed low over her eyes, glued to those ships.

It was enough to make Franky sigh, and the man swiftly blocked her view of the control panel and leaned back to pull her slim frame close. He pushed his sunglasses up on his forehead and quirked a brow at her expectantly.

For all Robin's restraint with showing emotion or concern, Franky knew that look tarnishing her features, and he'd seen it enough lately to warrant his own worries. Nothing good came from keeping those emotions in, so he waited the few moments for Robin to gather her thoughts, her slender fingers coming to play gently with the buttons on his shirt.

"What if we've endangered them, Franky," she eventually said, her voice soft but words heavy over the light hum of the boat's engine. "Suppose we made a mistake. Suppose we lose their trust-"

"I'm gonna stop you right there," he cut in, lifting a hand.

She let out a quiet huff at the interruption, but said nothing to protest, in fact ready and somewhat in need of his inevitable rebuttal.

Franky ducked his head until she lifted her troubled gaze to meet his.

Robin was easily the most intelligent person Franky had ever met, and yet it was pretty damn amazing how vulnerable she managed to look in that moment, how small and unsure when her every action did nothing but radiate power and decisiveness on a daily basis.

He supposed, in his more self-satisfied moments, that he was one of the few allowed to see this side of his girlfriend.

It was hard, times like these. What business did he have pretending to know better than her when she was always right? What business did he have trying to give _her_ advice when he was constantly rebuilding and rethinking his own self the longer he was with her? She challenged him that way.

But many things didn't change, the main one being that he _knew_ her. He knew Robin, and he knew that, despite being human, she _didn't_ put those she cared about in danger. Receiving Robin's vow of protection was of utmost security.

"The way I see it, none of this is a mistake," he assured, bringing hands to her hips where thumbs rubbed gently. His mouth screwed in thought for a moment. "Well, Zoro ramming himself into that propeller mighta been….and if Sanji-bro really did spill the beans to the Navy-"

Robin's eyes narrowed, lips pulling into an unimpressed line, so Franky quickly remedied his musings, pulling back from his rambling thoughts.

"But we wanted change," he justified. "And this way we can get it."

He shrugged, knowing he wasn't the best when it came to tactful persuasion. Still, his ways usually seemed to be enough for his girlfriend, who stepped closer and slid hands beneath his shirt to rest on his bare waist, almost waiting for the rest of his reasoning.

"I really do think Smoker and the chick got a good head on their shoulders," he continued, smirking when Robin quirked a brow elegantly. "Nami trusts her mom, and I dunno, I get the feeling Sanji-bro wouldn't've told anyone _he_ didn't trust."

"And suppose the entire World Government learns of them and sends scores of submarines to scour the ocean floor for the colony," Robin countered stubbornly, though arms circled his waist more firmly, and when the glint in her eye turned more teasing than worried, he knew he'd cracked the ice. She _wanted_ to hear his response.

"Suppose they are captured and held like animals, showcased and exploited, _test_ _objects_ just like the four held at-"

"The reason they were taken," Franky interrupted, recognizing this game. "Is because we weren't around to stop them."

He grinned the instant she let out a breath that was now fully amused, if under the guise of exasperation.

"It's not just us anymore," he continued while he had her attention, lifting a hand to brush some strands from her long ponytail back over her shoulder affectionately. "We got a lot of people on our side…." A beat and he risked a snicker, plus a disturbing thought. "Besides, I'm pretty sure Zoro could just eat Sakazuki if it comes down to it."

The sharp sting of nails pinching the skin of his hip followed immediately after.

"Never put that image in my mind again~" Robin warned pleasantly, leaving a painful pair of indents from her pinch.

Franky rubbed at the spot dramatically, but his grin was relaxed, and there was a light flutter in his heart when Robin leaned in first to pull him down for a gentle kiss to his lips, stroking fingers over his square jawline.

The embrace was brief, but the sentiment was there, and the smile on Robin's lips when they parted was enough to assure Franky of her returned confidence, particularly when the faint sound of another boat's engine cut the moment short.

Robin turned her head to glance behind them, out the open door of the cabin to the ocean beyond where, indeed, a small center console boat popped along the waves towards them, a trio of figures visible aboard.

Most curious was the clear mark of the East Blue Navy adorning the bow.

"Stop the engine. I'll handle this," she murmured with a final pat to Franky's waist as the boat slowed.

Robin left Franky at the helm and crossed the small room to step out onto the deck, their visitors pulling up alongside them.

"Greetings, civilians!" called a dark-haired man with a sprinkling of freckles across his face who crossed to the rail with a rather informal two-fingered salute under the brim of his cap, dressed in full Navy uniform. His smile was bright and charming to offset his rigid, militaristic stance.

"We're doing a bit of, uh, patrolling here!" the man continued, joined at the rail soon after by a taller man, tufts of blond visible beneath his cap. "You seen anything….suspicious going on around these waters?"

Robin's voice carried easily over the short distance between their boats, both engines having silenced.

"Other than one of the Navy's large vessels moving with haste towards M.A.R.I.N.E.S. Headquarters, no," she answered, smooth and honest.

She tilted her head in subtle calculation the instant the blond man leaned in to mutter something to the other.

Her calculation turned cold when she caught the word "O.H.A.R.A." leaving his lips.

The dark-haired man's brows shot up and his eyes locked onto Robin's with realization, followed by an immediate exclamation.

"Hold on, are you with O.H.A.R.A.?" he asked, nearly breaking his professional stance to lean forward eagerly. "Is Sanji Red with you by chance? From B.A.R.A.T.I.E.? Tall, blond, uh-"

" _May or may not be a fish_ ," muttered the third man at the helm, a brunette with a rather impressively styled goatee, to which the freckled man sang over his shoulder, " _Shut uppp~"_

Robin's observant eyes were quick to dart to the man's uniform, where the name 'Portgas' sat in crisp white font over the right side of his chest, beside the golden pin of a commander's position.

"He is not. Why do you ask?" she replied, despite now being certain this was the commander Nami had informed them of, the one who had apparently detailed the merpeople's existence to Whitebeard himself.

There would be no more information leaving her lips, however. Not until these men had proven themselves trustworthy.

"Well, I know you guys, uh-" stammered Portgas, Robin noting that it was clearly not within this man's abilities to hide the truth effectively.

To his benefit, the blond beside him, another commander with the name 'Phoenix' on his chest, interrupted more smoothly.

"We received word you were working together," this man stated, sounding far more assertive and self-assured. His voice was rehearsed though, words chosen carefully in a long-winded explanation.

"Dr. Red informed us the M.A.R.I.N.E.S. were removing some specimens in the area. They have yet to secure a permit, however. The admiral went to investigate the matter. We were sent to contact B.A.R.A.T.I.E. and monitor the-"

"As it happens," Robin cut in, electing to play along with the man's no-doubt fabricated story with one of her own. "We were notified as well and are now on our way to Headquarters in order to determine their exact intentions."

"Oh, are you heading to M.A.R.I.N.E.S. HQ as well?" asked Portgas, to which Robin leveled the man with a deadpan stare.

"Yes, I've just stated that."

"Perhaps we should escort you," Portgas offered swiftly.

Robin lifted a skeptical brow.

"Do forgive me if I'm wrong, but I was not aware the Navy acted as a police force. I'm quite positive we can manage on our own, thank you. These are free waters, as I'm sure you know. Passable for research vessels."

When the freckled man replied, his voice had lowered an octave in a poor attempt at deception.

"Well, we at the Navy can tell you these waters are also dangerous. Full of - sharks and…things."

"We have no plans to fall into shark-infested waters, Commander Portgas," Robin retorted with growing agitation. "And I do not see any rogue waves on the horizon either. We will surely be fine."

It was truly a wonder how someone with the subtlety of a person on fire could achieve such a high rank in the military, she thought.

Failing actor though he was, he was also persistent, Robin found, evident when, after but a quick flicker of fluster on his face, he shot back, "Yes, but we, uh, we at the Navy can ensure you smooth passage. Other ships must yield to us, you see. And you look like you're in a hurry?"

"We are," she replied, monotone. "So if you'll excuse us..."

"Yes, but we at the Navy certainly know a great deal about marine life too!" Portgas countered, hands, no longer capable of staying clasped behind his back, slapping onto the railing insistently.

The man jumped, however, when his blond companion elbowed him roughly in the side.

"And _we at the Navy_ should just let it go," he gritted out, though Robin was already prepared with her next comment.

"Do you now," she mused, admittedly with growing interest in the exchange. "I assumed the Navy dealt mainly with the euphotic zone."

Despite a quick glare in the blond's direction, Portgas was undeterred…and utterly unconvincing.

"Well, _I_ certainly take interest in that…zone," he assured with crumbling confidence. "You may not know this, but Sanji Red and I go way back so….I like….fish…too."

Beside him, a disgruntled noise from Phoenix, who had finally broken all professional composure to remove his cap and muss up the tufts of blond atop his head in long-suffering exasperation, a cringing grimace tugging at his features.

"That is to say that the ocean's habitats are of great importance to the Navy, Dr. Nico, and…"

The blond's attempts to translate 'Foolish', while admirable, ultimately proved fruitless when he let out another huff and seemed to give up with a shake of his head.

It was quiet then, both men lost for words and not finding them when Robin's gaze only narrowed, looking between the still nervously broad smile on the freckled man's face and the shining disappointment hanging over the blond's.

In her peripheral, Robin saw Franky approach the rail as well, thick arms crossing over his chest.

"Commander Portgas," she finally said, not bothering to mask the judgment in her tone, eyes moving smoothly between the two men. "Are you and your pineapple brigade trustworthy individuals?"

The freckled man's head lifted, wide eyes meeting hers for a moment…until the smile slowly fell from his face, and it was Robin left surprised at the sudden serious severity that had so quickly replaced his bumbling demeanor.

Suddenly, she was amazed to find a true soldier before her, whose voice was bold and decisive when he replied, "I'd kill anyone who tries to hurt Sanji."

Robin practically felt Franky's shock beside her, certainly felt his gaze shift to her, despite her own remaining on Portgas, who did nothing but stare back with smoldering conviction.

It seemed Franky was too impatient to wait out the long moment Robin remained silent.

"You guys packin'…?" asked the man.

A soft snort from the blond.

"As military officials, yes, we are required to carry certain firearms in case of-" the blond replied, but Portgas cut him off.

"Hell yeah we are," he stated, still with that pointed gaze on Robin, a silent message passing between them.

Franky nudged Robin's arm gently with his elbow.

She sighed, hand finding her temple where it rubbed.

"Commander Portgas," she addressed, voice finally losing some of its edge in favor of slight exhaustion. Franky had been right, after all. They were no longer alone in this endeavor.

"I will refrain from causing your honorable death in the line of service," she conceded, however reluctantly. "Along with your dear indiscreet friend, Mr. Red. I will deal with you both when our more pressing matters are taken care of. Now, since you are _so_ inclined, you may lead the way."

With that, she turned on her heel, tugging Franky's shirt gently to drag him back to their vessel's cabin, pretending she didn't catch a glimpse of a triumphant fist pump, nor hear the blond's disgruntled mumble of, "Pineapple brigade…?"

* * *

 _ **North Blue**_

* * *

Zoro remembered.

It had been a fine day just like this. The sun had cut curtains of light through the water, catching the scales of countless fish, sparkling glints in the blue. It had been perfect for hunting, and apparently he and Kuina hadn't been the only ones to think so.

Because the dark cloud that had come overhead that day had been the very same, Zoro now realized, remembering this exact deck vividly, remembering how huge and _blinding_ it had seemed, how his shoulder had stung from the heat when he hit the deck hard, wrapped in netting and struggling madly to be free.

There had been no salvation. There had been no bracelet, and when Kuina had disappeared into a hatch in the floor, he'd been left terrified and alone for his last minutes of consciousness.

It was impossible to forget.

So Zoro's eyes stayed fixed on the sea, that endless blanket beneath which stretched freedom.

They sat mere feet from it, he and Sanji, the two of them tense where they'd settled, on a bench against a wall on the lower deck, wary eyes shifting about, though no one seemed keen on bothering them anymore, aside from the occasional crew member who glanced their way.

It would be so easy, as it hadn't been with Kuina, to take Sanji and escape. The ocean was so close, and every instinct in his body screamed for him to leap right over that rail to what was surely safety.

But that would be _too_ damn easy, wouldn't it. It would change nothing. The M.A.R.I.N.E.S. would be right back on their tails, and even more lives would be at risk.

It would be too easy and yet he _wanted_ it, selfishly. Not for his own safety, but for Sanji's.

So what if they were in danger? The ocean was fucking massive. They could relocate, or….or…

"I'm not afraid of him, Zoro."

Sanji's voice beside him, perhaps the only thing that could tear his gaze from the sea.

Zoro turned to look at him, practically trembling now with the adrenaline still coursing through him with no destination, confused now that there was no fight, but also no flight.

The blond was hunched over his knees, staring hard at the deck until he let out a resolute breath and sat up straight to look back at Zoro with a strength the merman didn't feel he possessed in that moment.

"I _can't_ be afraid of him," Sanji finished to Zoro's face, though it seemed to be more of a mantra for himself.

With nothing to say, the merman reached out to take Sanji's hand with a heavy sigh of his own, lacing their fingers and squeezing tight with any hope that this would fucking be alright.

To his surprise, Sanji let out a quiet chuckle.

"You're good at that," said the blond, who lifted his free hand to card through Zoro's hair, smoothing back some of his still-damp spikes.

"Huh?" Zoro stuttered, mouth going a little dry.

"Sighing dramatically," Sanji clarified with a pointed smirk. "Just…funny, considering…."

But he shook his head and trailed off, seeing Zoro's face, which didn't even crack a smile in return, the merman looking more troubled and resigned than he'd ever felt recently, despite his faith in Sanji.

"Hey," murmured Sanji, his brows furrowing in concern. "You okay?"

Fingers stroked a little more urgently before he pressed the back of his hand to Zoro's forehead as he had that first morning on the boat ride to O.H.A.R.A.

It wasn't the heat though. Not this time.

"I remember," Zoro said, his voice and memories completely clear.

Sanji blinked at him for a moment, then leaned in a little closer.

"Remember…?" he replied, searching Zoro's features.

Zoro met his eye again, choosing to look where the future was in view, not the past.

"This ship," he said.

At that, the blond sucked in a breath, eyes flicking to their surroundings.

Zoro watched him until, a second later, he saw the realization hit, Sanji's eyes now widening a fraction before meeting Zoro's again in dismay.

The merman nodded, jerking his head slightly to the deck behind him without looking away.

"There. Kuina. They…."

A vague gesture that implied what he couldn't formulate in human language. That horrible moment he'd seen her disappear. That moment he'd assumed it was over.

Immediately, Sanji tightened his grip, squeezing Zoro's forearms then sliding hands down to grasp his.

"When all this is finished," he implored, voice hushed, but strong. "When the M.A.R.I.N.E.S. are no more… I'll burn this ship. And all of its memories."

For some reason, whether it was Sanji's words or his very _presence_ , Zoro suddenly found it harder to breathe, a tingling sensation in his chest, particularly when Sanji's lips tilted up and he asked, "You ever seen fire before?"

Fire. That brilliantly bright heat that overtook everything in its path with its gracefully deadly, almost liquid, power.

Sanji's eyes held him with that same mesmerizing warmth, which spread through his body, had him licking lips unconsciously and nodding.

"Yeah," he breathed, staring directly into that fire now, and he saw Sanji's eyes automatically drift to his lips where they stayed for a long moment.

The blond lifted a hand to Zoro's jaw, touched delicately, his thumb stretching out to brush over Zoro's bottom lip.

Zoro stayed firmly still with almost shy hesitation, certainly anticipation, that he hadn't felt, not in the same way, in his normal form. His breaths came unevenly, and his heartbeat picked up speed.

Frustration became palpable on Sanji's face for a moment, for reasons Zoro wasn't sure of. But the blond let out a huff eventually and glanced quickly over his shoulder at the now empty gangway.

They were alone.

Then the blond turned back to Zoro, muttered, " _Fuck it."_

And then their lips had met in a clash that made the entire outside world drop away to nothing the moment Zoro's eyes closed automatically, his hand finding its grip in Sanji's hair.

This was different. This was entirely different to kissing Sanji as a merman, Zoro quickly discovered. It felt almost more urgent, more desperate, and his senses felt heightened, Sanji's lips sending pleasant clenches of electricity that seared through his chest the longer they kissed.

There was more to taste, more to feel, particularly in Sanji's hot breaths over his lips, which tingled, wanting more in the instances he pulled away.

His chest had begun to burn, and he wondered if it wasn't because of Sanji's hand, skimming over his beads to land on sensitive skin that, for some reason, now seemed to silently urge him downward alongside the shiver that ran the length of his spine.

It was overwhelming, suffocating, for a few moments until Sanji knocked his fist into Zoro's chest with a muttered reminder of, " _Breathe,"_ prompting Zoro to suck in a quick breath he'd forgotten he needed.

Sanji only gave him a few seconds of recovery, however, before he stole that breath again, not that Zoro was particularly complaining.

He didn't know what this was. He didn't know why his brain seemed to become even fuzzier than it had the other times they'd kissed.

He didn't know what this feeling was, this tenderness and soft affection that he'd never felt, nor been _capable_ of feeling. The way his emotions started to feed into his lips, seemed to want to say more to Sanji than he had yet, trivial things that didn't matter, but _did_ now, if only he had the words.

He didn't know why, but it was suddenly making some semblance of sense, why he always saw Franky and Robin kissing. Why humans did it so damn much in their weird movies.

And then all too soon, Sanji was pulling away again, with another knock to Zoro's still chest.

"Again, idiot. You keep forgetting," he urged, though he was smirking by the time Zoro remembered, breaths finally coming again in heavy pants.

A snicker and the blond leaned in to kiss the corner of Zoro's lips, knocking his nose to his cheek.

"We'll practice," he murmured in Zoro's ear, his tone teasing enough to force an eye roll from the merman. For all Sanji's jabs, the asshole sounded pretty damn breathless too.

Sanji nuzzled close for another minute while the both of them calmed, Zoro bringing hands to Sanji's waist.

It felt easier, far more natural to reciprocate like this. Even if he had no idea what he was doing, his now fully human instincts seemed to better understand this side of him, and maybe better understand the blond's frequent affection.

"Thank you, Zoro…" Sanji said eventually, forehead knocking against the merman's, where he closed his eyes. "You didn't have to come with me."

Immediately, Zoro shook his head in response, a soft grunt of protest leaving him.

"Did - have to," he insisted. He had to for so many reasons, but especially this new one, whose lips turned up before he tilted his head to kiss Zoro again, just gently.

Despite remaining in enemy territory, Zoro and Sanji both fell into silence, holding onto each other's presence for support, oblivious to the crewmembers who witnessed, with some degree of shock, their display of intimacy…

* * *

The remainder of the trip passed in relative calm, the two of them regaining a bit of their rationality and watchfulness the further they sailed into the unknown.

Sanji didn't know what to expect, having never been to M.A.R.I.N.E.S. HQ, and he _hated_ that he now knew the reason. Now he knew why all correspondence between them and B.A.R.A.T.I.E. had taken place solely over the phone, or online.

He felt stupid for never having questioned it, and despite the welcome distraction of the comforting kiss he and Zoro had shared and his own declarations of bravery earlier, the fact remained that he was traveling to the place that had held his brothers prisoner for their entire lives.

He was traveling to the place where his mother had likely died…

Thus, that first hazy glimpse of land on the horizon before them did nothing but send a host of protesting butterflies swarming through his stomach, every inch of him filled with cold dread.

Zoro seemed to sense his discomfort, for the merman took his hand as that blur of land grew clearer, crew members now moving with increased pace to prepare for docking. The merman held it tight, his features sharpened with determined focus.

The blond closed his eyes, forcing that same focus into his own mind before he stood, Zoro following, the two of them walking the few paces to the rail for a better look at their heading.

Below them, the water gleamed a lighter turquoise as they approached the shallows, and what stretched before them was not the proper coastline, but a smaller island, a white sand beach visible, topped by the brilliant emerald of swaying trees.

And there, its own island amongst the green, was an imposing circular building, built in tiers that towered above the canopies several stories. From its base jutted a series of piers, stretching like claws out into the water where, already, Sanji could see a number of vessels docked, none quite as big as the one on which they sailed now.

It looked a haven, surprisingly, a paradise of sorts, the vegetation lush and healthy, the surrounding water clear, colorful coral visible beneath.

The pier they approached was large and impressive, sturdy white wood, staircases casting down to the smaller vessels.

Sanji's hands gripped the railing harder as the ship began to turn, swinging portside towards the pier's end in order to dock, men ashore, dressed in the same white uniforms, already preparing ropes to secure them.

There was no joy in the process, no excitement or friendly banter, just a mechanical routine among the crew that seemed devoid of life, of the passion for the sea Sanji knew his own tiny crew at B.A.R.A.T.I.E. always enjoyed.

And it wasn't until the boat finally stopped, bobbing in place beside the pier, the gangplank lowered, that Sanji was even aware the captain had emerged onto the deck.

Not until he heard Zoro growl and shift, just before another figure appeared on his opposite side.

"Welcome to Marineford Island," Sakazuki rumbled coldly, hands, devoid of cigars, clasped militantly behind his back. "If you'll follow me."

Sakazuki stepped away, towards the deck where the gangplank now connected the ship to the docks, and Sanji realized they had no choice but to follow, a few other crew members appearing silently, but threateningly, behind them.

So the blond clamped a hand down on Zoro's forearm, guiding the merman along, carefully over the wobbly gangplank until feet, still bare, touched down on the warm wood of the dock.

Sakazuki didn't look back, merely began walking down the long stretch of the pier, which converged with the other jetties before the entrance to the building, a broad set of white doors above which the M.A.R.I.N.E.S. logo was painted, large and far too blatant for Sanji's tastes, as if they didn't already know where they were.

The blond spared a glance at Zoro, who met his eye, but nodded subtly in support.

Sanji nodded back, and then they were moving again, following Sakazuki's heavy plod, the image of a pirate plank vivid in Sanji's mind with nothing to do but focus on the great abyss before them.

It was a few dozen meters or so, but it felt like miles, Sanji's heart pounding the entire way until they reached the end, Sakazuki gesturing them onward up a flight of stairs in front of the entrance.

He glanced expectantly at his two guests, eyes trailing up and down Zoro's form for a moment before starting up himself.

Sanji paused at the bottom of the staircase, turning to Zoro with the intention to help him, but the merman already had a determined hand gripping the wooden railing, tentatively lifting one foot to place it on the first step.

Stairs. It was something Zoro had never done before, but for all his bitching about walking a short distance the other night at B.A.R.A.T.I.E., the merman seemed completely resolute now, looking at Sanji, waiting for his assistance.

The blond let out a breath and glanced up.

Fifteen steps. They could do this.

So he brought a hand firmly to Zoro's waist, the other hovering over his back, and they began their clumsy ascent, receiving no help from their hosts.

The climb was not without its stumbles, the merman losing his balance several times, a palm slamming down onto steps above to catch himself more than once. It was shaky and slow, and had they been anywhere else, Sanji would have been laughing his ass off.

But somehow, they managed, the two of them slumping onto the top landing finally, Zoro breathing heavily.

And despite the fact that Sakazuki stood nearby, waiting, stoic, by the doors, despite the fact that freedom and safety was now far below, Zoro and Sanji both found themselves cracking triumphant grins, the merman bringing a hand to his mouth to try and hide it.

Only to have that hand grabbed tightly, wrenched back from his face and twisted behind his back by one of the grunts who'd followed him, the other quickly tackling Sanji and dragging him back towards the doors to the building.

Sanji's heart leapt into his throat, a cry of alarm escaping him.

"Get your hands off me!" he snarled, thrashing and lashing out with a leg that couldn't quite reach his attacker, the man's grip strong and his arms pinned.

Behind him, the heavy doors began to slide open, Sakazuki standing calmly to watch for a moment before he beckoned towards the interior and stepped out of the sun into the shaded building.

Sanji struggled to get his footing, get on his feet at least so he could have some traction against this bastard and help Zoro.

They were alone. _Fuck_ , they were alone, and why the _hell_ had he let his guard down? How the _fuck_ had it come to this - the fact that he'd been stupid enough to think that maybe, just maybe, he had a chance of civil negotiation here.

He couldn't hear, couldn't see through the blind panic that wracked his body, terror he'd never felt before.

Until Zoro's voice brought him back, gritting out his name, the blond's wide eyes falling immediately on the merman, whose arm was yanked up at a painful angle, his attacker with a claw-like grip on his wrist.

Zoro's eyes met Sanji's, his panicked huffs fast and frantic.

And to Sanji's absolute horror, the man swiftly unclipped the bracelet from Zoro's wrist, throwing his arm down and stepping over him like he was worth nothing.

The world slowed, Sanji's kicks and thrashes futile as the second man pocketed the bracelet and joined the first in subduing him, pulling him back into the building with renewed force.

His own voice sounded dull and distant, his screams for Zoro to escape, get back to the water as skin disappeared and that green tail sprouted anew.

Zoro didn't listen though, the merman flipping himself to his stomach, teeth clenched in a grimace and arms trembling with the effort to drag himself across the landing towards the doors.

His voice was nothing but a choked whisper.

" _San - ji-"_

Zoro's struggling image outside was swallowed up by that narrowing crack of sunlight.

Tears were hot in Sanji's eyes as those doors slammed shut between them.


	12. The Bridge

Water.

Zoro needed water, but all around him was the searing heat of _air_ on his gills, and those closed doors in front of him, through which Sanji had just been dragged, screaming his name.

No. _No_. It was just like Kuina, but he _wasn't_ helpless this time. He couldn't be, didn't want to accept it, and yet he _was_ , alone, thrashing and burning alive, unable to breathe.

The water was there though. Far, below the pier, down those stairs. He could have mustered his strength, could have probably - _hopefully_ \- thrown himself over the edge, hoped to maybe land in the water and not on one of the boats bobbing below. It was a longshot, but there was a chance.

 _He_ had a chance, but did Sanji?

He _forced_ himself to move.

And yet, not towards the sea, as Sanji had so desperately urged him before disappearing.

Instead, he moved towards those doors, an irrational determination fueling him, placing Sanji's wellbeing above his own, even if it risked his life.

It was useless, he knew. He could tell it was because his arms could barely pull him. His body wouldn't cooperate, suffocating, and the hot surface of the metal landing beneath was roasting every inch of him.

Still, his fist punched the door, once, twice, through the spasms that wracked him, skin feeling ready to blister and crack from the dry heat surrounding him.

" _San - ji-"_ he gritted, heart racing, refusing to let his vision tunnel, using all of his willpower to stay conscious, ignore the pain.

He was the only one. He was the only one who could help Sanji.

This was the thought in his mind as his arm finally fell limply to the floor in front of the door, though mentally he was still pounding.

He vaguely heard voices below, on the pier.

"Give it another ten minutes. Just to be sure."

It was too far though. Everything was too far. The water…..Sanji….

He wasn't going to die. _Fuck_ that. Fuck…

He would fight with everything he had.

Fight until he—

Until it—

Fight—

Just—

Fi—

…

* * *

Sanji found himself putting up the biggest fight of his life, lashing out at the two men who held him, with his fists, legs, _anything_ to be free because _Zoro_ was outside. They'd stolen his bracelet, beaching him essentially, and Sanji could _not_ let this happen. He _would not._ Zoro wasn't _allowed_ to die.

"Let me go - let me _go!"_ he cried, unconscious protests and gritted hisses of Zoro's name catching in his throat the further down that hallway they dragged him.

He couldn't even take stock of his surroundings, just that pair of white doors ahead that grew smaller and smaller by the second.

He was strong. He was stronger than this, surely. He could _defend_ himself, dammit, if he just quelled his fucking panic and _focused_ , but it was only Zoro's face in his mind, his dark eyes wide and scared, an expression he'd never quite seen from the merman.

And _no one_ was coming to help them, surely. Not in time at least. He knew Zoro had mere minutes.

This thought alone was enough to send him struggling anew, but his captors merely coiled their arms tighter under his.

He heard Sakazuki's voice behind him, low and calm.

"If he's going to fight, restrain him."

And then, unexpectedly, he felt a hard shove on his back, and the men slammed him into a wall, hard. His shoulder caught him, with bruising impact, one of the attackers clenching fingers roughly in his hair to push his head against the painted concrete too, with enough force to gray his vision for a few moments.

But adrenaline and instincts kicked in tenfold, and Sanji used that wall as momentum to twist himself, even as they wrenched his arms painfully behind his back.

Until he felt the sharp plastic of a cable tie quickly binding his wrists.

His captors' movements were practiced, the two succeeding in their task despite his attempts to roundhouse kick each in the stomach. It was frustratingly clear that they'd dealt with aggression before.

Sanji didn't have time to ponder just what that fact meant, however, before he heard, "Change him," followed by a telltale pair of prongs digging into his restrained wrist, the bracelet clamping on.

And then, legs were unable to support him because they didn't _exist_ , the blond going rigid and slumping to the floor with a pained grimace as heat crept up his entire body, from his fusing toes, over his shorts, to his hips.

By the time it reached his chest, his breath was sucked out of him and his tail whipped frantically, searching instinctively for water, gills burning with a fire more intense than when that net had pulled him from the sea.

He couldn't breathe, and he could no longer fight back at all when one pair of arms grabbed his torso, the other his tail, lifting him and carrying him off to fuck knew where. He couldn't even control his body anymore, spasmodic twitches and contractions of pain coiling his upper body time and time again.

Sanji was only aware of blinding fear, the likes of which he'd _never_ felt, absolute panic.

Claws of pain tore through every inch of him, every bit of contact with his dry tail feeling like sandpaper filing away on his bare skin, and the air was a merciless blowtorch on his gasping gills.

He was going to die. He was going to die. There was no way around it. There was no one here to help him, no water, no air - fuck, he couldn't even _take_ a breath and Zoro - Zoro was-

Zoro needed - to get - to the water and - there was no water - there wasn't.

There was no one. His dad would never - shit, air, water, _something,_ _ **anything**_. _Fuck_. He hadn't meant for - _air_ …..air…..please….

His vision began to darken, no more flashes of fluorescent light overhead, disorienting and sinister with its clinical glare.

He was burning—

He was dying—

Zoro—

…..

….

…

Blue…

He was breathing, but it hurt, gills sore and aching…

Everything ached. He was exhausted. His head was fuzzy.

He was surrounded by water.

A cyan glow.

But his mind was falling to black once more.

Even though he had to save…

…

…he couldn't…

…

…Bubbles…

…

Black…

* * *

 _ **B.A.R.A.T.I.E. – East Blue**_

* * *

Zeff remembered the little eggplant's first day of kindergarten as a child.

He remembered the boy hadn't been afraid to go. He'd been excited, annoyed his dad the entire night before with plans for his outfit, rearranging the contents of his little backpack over and over again, checking that his dolphin keychains were attached, making sure he had everything he needed, even if, at five years old, all that was really necessary to bring was _himself_.

The boy hadn't been nervous, not even in the morning, when he'd been the one to demand his dad take his picture by the front door, a gap-filled grin on his face as he sported his new favorite blue sweater vest and mini clip-on tie, because it made him look like the grown-up he felt like.

Sanji hadn't been nervous during the entire car ride, bouncing in his seat, swinging short legs, and peering out the window eagerly as they pulled up to the school.

He'd popped out of the car with a spring in his step when they'd parked, gathered his things and shouted, "Bye, geezer!" despite ultimately having to wait for said geezer to walk him to the door, as per the rules.

They'd reached the kindergarten entrance, already busy with parents and children.

And Zeff remembered his son's eyes had gone impossibly wide when he realized every last one of those children looked, not excited, but terrified out of their minds.

Children were clinging to their parents, wailing in protest as teachers tried to gently coax them away. He saw tears streaming as those that accepted their fate trudged to the doors as if walking to their dooms.

He heard the whimpers, the desperate pleas to stay with their parents, and it was enough of a scene to stop the young boy in his tracks, claw up a sense of sudden dread in his chest, watching those kids be dragged inside one by one, arms reaching for freedom.

He'd looked up at his father with burgeoning apprehension.

But Zeff had merely grumbled about how terribly other parents were raising their kids, clapped a hand on his shoulder, and urged him forward. The boy was far more well-mannered and complacent than those other little brats, who'd put up such a damn fight. He would obey authority.

Sanji had stared silently at his dad as a teacher led him inside, putting his trust in the unknown with a small wave.

Zeff had stood there until the doors shut, letting him go with faith that he would be just fine.

This is how it had been with most things in Sanji's life, always. He let the boy be independent. He let him make his own decisions, make his own mistakes, without fear of how it would turn out.

But it was always with that underlying worry, that conflict under the surface between the want to give him freedom and a normal life….and the knowledge that a distant danger lurked.

It had been a few hours since Sanji had sunk beneath the sea that morning, against his father's wishes.

And as Sanji dove to the depths, every fear Zeff had ever had in his life rose to the surface.

Sakazuki was out there, searching for his escaped merfolk. And-

"Hey, boss."

Zeff looked up from the ropes he'd been pulling tight with far more vigor than necessary, the painful burn of his palms a welcome distraction from his thoughts.

Across the deck, at the bow of their small vessel, stood Patty, a hand over his eyes to shield them from the sun as he looked out at the ocean's horizon.

Their boat still bobbed at B.A.R.A.T.I.E.'s dock. They'd simply been running a few maintenance checks, at Zeff's request, a poor excuse really, unbeknownst to Patty and Carne, for Zeff to keep an eye out for Sanji. They didn't yet know what he was, and Zeff had told them he'd given Sanji the day off, the boy out to see his friends for once.

But B.A.R.A.T.I.E.'s small crew were seafarers at heart, and docked or not, when there was a deck beneath their feet, they were ever watchful and aware of the surrounding ocean.

So Zeff too instantly noticed the large fuzzy shape on the horizon, easily missed, but not by a sailor.

Zeff stood, having secured the tool boxes beneath the boat's bench, and he plodded the short distance to Patty's side to have a closer look.

Yes, that shape was definitely a ship, a rather large one at that, dark in color, and there were only a few ships that large and that dark in the area, Zeff knew.

All of them belonged to the Navy.

Confirming his thoughts, Patty lowered his hand and crossed arms over his chest.

"What's the Navy up to today?" Patty mumbled, scratching at the sweatband he'd snapped around his bald head.

Zeff's eyes narrowed.

It could have been any number of things. After all, despite these being peaceful waters, Navy ships did frequent the area for training. It wasn't out of the ordinary.

But the fact that the ship was sailing north…at the same time Sakazuki was known to be scouring the East…

Perhaps his nerves—the tension he felt over his missing son - were simply getting the best of him. It could have been nothing….but the sight did not sit right with Zeff.

"We'll be needing to check the eel traps on the reef," he eventually said, ignoring Patty's question entirely, though his eyes stayed firmly fixed on that horizon. "Let's get ready to cast off."

Patty stared a few seconds longer, then shrugged with a sigh, shaking his head a bit, and turned away.

Zeff stayed where he was though, still and statuesque at the bow, the sound of Patty and Carne bickering in the background as the two men set about their preparations.

He stood there for a minute longer, watching the waves.

And that was when he saw a head pop up in front of the breakers, wet hair concealing one eye.

For a moment, Zeff's eyes widened in surprise.

But it only took him another moment to notice that hair, even wet, held a distinct rosy color. Definitely not blond.

And then a flash of a pink tail, and the visitor disappeared beneath the surface once more….until, some thirty seconds later, the mermaid re-appeared directly below him in the water, bobbing there with a look of cool conviction on her face.

He leaned over the rail to meet her eye, brows furrowed in his usual resting face.

"Are you Dr. Red?" the mermaid asked, and her voice, her features, everything took him right back to that fateful day, when he was decades younger. To the unsuspecting day when another mermaid had appeared in the exact same fashion, with those same blue eyes that he saw every day when he looked at his son.

"I am," he grunted, and he needed no introduction from her, already knowing who she was before she spoke.

"My name is Reiju, of the East Blue colony," she said, and though she closed her eyes to compose herself, she opened them again with determination to state, "It's Sanji. He was taken by the M.A.R.I.N.E.S."

Zeff's terror finally breached the surface with the force of a leaping whale.

* * *

 _ **North Blue – En route to M.A.R.I.N.E.S. Headquarters**_

* * *

"Look, don't blame Sanji for all this. It's not his fault."

Robin sighed, eyes on the man, by the name of Ace she'd learned, who'd quite easily made himself at home on Merry's deck, the freckled man leaning up casually against the cabin's door frame.

They were making pace again with Franky at the helm, Ace's own vessel moving along beside them, his two crewmen in control.

But Ace had been rather quick to make the leap to their boat, clearly with a mission in mind.

"Mr. Red was sworn to secrecy when he visited us," Robin stated. "And now the admiral of the East Blue Navy knows everything-"

Perhaps it was useless to debate at a time like this, but the worry was still there.

"Yeah, but I was the one who told Admiral Whitebeard," Ace justified. "Sanji was right to trust me! I only told people _I_ trust!"

Behind Robin, Franky snorted in amusement.

Robin ignored him, instead blinking slowly at Ace, hoping her silence was enough to express how utterly ridiculous she found his argument. And it seemed to work to a degree when Ace wilted somewhat, reaching up to rub at the back of his neck anxiously.

When he spoke again, his smile had become more sheepish, tone more serious.

"It was 'cause of his dad," he explained. "His dad wasn't gonna let him help the merpeople - shit, that's still crazy to say." A tiny smirk, but he sighed. "And Sanji was sayin' shit like - he was gonna fix this. He was gonna talk to the M.A.R.I.N.E.S. but….he said people had _died_ and I just - I dunno, I couldn't just sit by and let him put himself in harm's way! I panicked! And I know Whitebeard can get shit done-"

Despite Ace's sincerity, Robin was quick to retort.

"And if this news spreads to the government?"

But to her initial confusion, Ace's lips curled up, flashing teeth, a brow quirking mischievously.

"You must not know how Whitebeard got this job," he replied.

Robin's eyes narrowed, not intimidated if this was an attempt at condescension.

"Do enlighten us, Commander," she said.

Ace shrugged dramatically, holding up hands with a grin.

"Let's just say Whitebeard saw some shit, back when he was a drug smuggler out on the Grand Line. Yeah, that's right. He was, a couple decades ago~" he explained proudly when Robin lifted an eyebrow in subtle, and perhaps skeptical, surprise. Still, she waited for him to continue.

"He saw some shit he wasn't _supposed_ to… Government paid him off to keep him quiet. Set him up with a job in the Navy. Figured he was better off takin' out enemies rather than the feds."

"He saw merpeople?" Robin immediately asked, wondering if the Navy hadn't been aware this whole time.

But Ace shook his head, unable to help a teasing wiggle of brows.

"No. Think opposite," he said.

Robin frowned, her mind instantly filling with possibilities.

"My point is," Ace continued, bursting through Robin's thoughts of strolling humans, sailing the seas with the heads of fish. "Whitebeard knows what's right and wrong. And he knows when to keep his mouth shut. Even from the government. I trust him more than anyone. We all do. And if Sakazuki's up to no good, he won't let him get away with it. _You_ can trust him too."

He spoke the words convincingly, an easy, and yes, trusting, smile on his face, despite the known difficulty of the situation at hand.

Robin's gaze flitted to Franky, knowing she felt the very same for her significant other. And she'd been able to trust Nami, who she'd allowed to alert the West Blue Navy.

She was also fully aware of the faith she'd had in Sanji, particularly after observing _Zoro's_ trust in him.

"And Mr. Red trusts _you_ ,"she said out loud, deciding to use it as justification for herself. They could have these people on their side, and they would succeed.

"Well, that's what happens when you get to know a guy naked," Ace shot back in reply, grin spreading even wider.

Franky's cackle exploded in the small room over the sound of the boat's motor, billowing out of the cabin's open windows.

"Right on, bro!" he said over his shoulder, still chuckling, with a massive thumbs-up.

Robin's palm elegantly met her face.

"Don't worry about it," Ace assured her, clearly thrilled to have amused the other man. "We've both moved on. Other fish in the sea, y'know?"

Then a wink, followed by more raucous laughter from both men that now left Robin with the scarring image of a certain green-haired fish receiving a head of a different kind…

She sighed, deciding to leave the men to their devices as the two began a spirited conversation regarding arson and explosives that may or may not come in handy for their visit to M.A.R.I.N.E.S. Headquarters.

Her gaze settled on the open sea out the window, Ace's vessel hopping over the waves in her peripheral.

It was peaceful, aside from her concerns, and she tried to focus on that instead, the warm breeze, the rushing of the water….until the buzzing crackle of the boat's radio sounded, enough to instantly capture the attention of all three passengers.

Robin's eyes automatically met with Franky's before she hurried to the console on the control board.

The instant she pulled out the receiver, a frantic voice came through, in a foreign language, but one Robin understood well.

" _Robin! Franky! This is Reiju - do you copy?"_

Robin's eyes widened, the mermaid perhaps the last on the list of those she would expect to call. How she'd even come into contact with a radio was also a mystery.

Still, Robin composed herself enough to answer quickly in the same tongue.

" _Your Highness! Is everything alright? Where are you-?"_

 _"At B.A.R.A.T.I.E.,"_ Reiju shot back, clearly with little patience….or little time, the reason behind which soon became obvious when she blurted, " _Sakazuki took Sanji and Zoro! They were heading north!"_

And dread instantly filled the room, Franky's head whipping towards Robin now. He wasn't fluent in the merpeople's language as Robin was, but she could tell he'd registered the suddenly dire situation.

Even Ace, predictably confused by the exchange, picked up those two names, as well as the panic in that voice.

Robin inhaled sharply, quelling her own panic in favor of a fast reply.

" _Franky and I are currently positioned in North Blue, on our way to Headquarters as we speak,"_ she assured, followed by an urgent, _"Please stay out of harm's way!"_

A few parting words from Reiju, and Robin hastily replaced the receiver, already bracing herself against the control panel because Franky knew what to do.

His brow drew in tight, and he plopped a hand onto the throttle, flooring the boat forward quickly in the water.

"Whoa, what's-!" Ace stammered, grabbing the doorframe to keep from toppling over. "What was that about Sanji?!"

"You said you were prepared to kill should anyone harm Mr. Red," Robin replied, hair as dark as her tone whipping a storm around her face as they picked up speed.

Ace's eyes narrowed, lips slowly pulling down into the beginnings of a scowl.

"Sure am," he answered smoothly, ignoring Marco's voice calling his name over the wind and waves behind him.

"Well, you might have your chance," Robin replied. "It seems he's been taken."

That was all Ace needed to hear.

The freckled man whirled around, flying the few strides to the railing where he yelled, "THATCH! GET YOUR ASS IN GEAR," to his own boat, hurrying after the Merry in confusion.

Marco, already on the deck, a hand on his cap to keep it from flying away, called back, "What's going on?!"

Burning rage filled Ace's chest, and he knew Marco felt it too when he shouted his explanation.

"They have Sanji!"

* * *

 _ **M.A.R.I.N.E.S. Laboratory Headquarters - North Blue**_

* * *

The quiet rush of water filled his senses, held him, suspended, in that cyan womb that pulsed like a heartbeat, his own beating placidly in his chest. His gills let in smooth rushes of water that felt as soothing as a deep breath.

Sanji opened his eyes, and it was almost dreamlike, to awaken in water, fully able to breathe and see. He might have panicked, but it was calming enough that he didn't for a long minute, almost hypnotized by the sensation, so much that he wanted to float there forever, amongst the steady stream of bubbles that flew from a clear tube stretching down from above.

His tail swished lazily, and he reached out a hand, seeming to glow a pale blue like the water itself. He forgot to even question the fact that his hands were free in the first place…

And his palm met, unexpectedly, with glass.

Instantly, he jolted, his body going rigid, and his second hand jutted out to meet the same glass before him.

His eyes widened, hands scrambling in every direction around him to find that it encircled him on all sides, a thick glass cylinder that he now realized imprisoned him and-

Zoro.

 _Zoro._

 _No!_

He was screaming it out loud before he knew, fists slamming on the glass, whirling in circles for something, _anything_ that would help him escape.

But there was nothing; he couldn't even extend his arms fully in the claustrophobic space.

So he gave a flick of his tail and swam up, stretching arms above him…

And his palms, despite breaking the surface a few inches, hit metal, effectively sealing him inside the cylinder.

Panic. _Again._ Would he ever _not_ feel it?

Frustrated growls left him as he tried, frantically, to push that metal away, to no avail.

There was no way out, and how long had he been here? For how long had he lost his senses?

If Zoro hadn't gotten himself back in the water, it was impossible for him to still be- No, he couldn't have-

 _Fuck_.

Sanji cut off every terrible thought that ran through his mind, slamming fists, his shoulders, his tail, against the tank's walls with any hope of shattering them.

Over and over without so much as a crack in the glass, or a dent in that metal cover above him.

Minutes ticked by, Zoro's chances shrinking with each, and it was _his fault_. It was all his fault. Yes, Zoro had come voluntarily, but this had been _his own idea_.

He hadn't realized - hadn't heeded the warnings - hadn't actually thought the M.A.R.I.N.E.S. capable of such evil. He'd been told those stories, but he'd thought he had a shot, that surely this wasn't like the movies. Things couldn't be this bad so close to home.

But they were, and when blood began to wisp through the water from his fists, hands and arms throbbing painfully from his efforts, he felt himself sinking, powerful shivers running through his body.

His gills pulled in great gulps of water, and he curled in on himself when his tail hit the tank's floor. His shoulders shook with sobs that brought no tears but still immense sorrow.

He was powerless and weak, and all he could think of was Zoro, who had given him so much in such a short time.

What he'd felt with the merman had been new. Zoro had challenged him; Zoro had understood him, been fascinated with him in ways no one else ever had. He had come from a different world, but they'd connected almost instantly, and surely what they had could have grown….it could have….

But…

" _You have to fight -_ _ **please**_ _fight. Please, d-don't-"_ he hissed, pressing his face into his arms and shuddering, knowing words alone were useless.

If Zoro hadn't reached the water by now…

"Mr. Red."

A deep, muffled voice shot an icicle of fear through his heart, and he startled, eyes shooting open, only to notice a new blur of colors behind the glass that became clearer when he focused his vision.

Sakazuki was standing directly before him, looming over Sanji's curled form calmly.

Sanji had dove in aquarium tanks in the past, tending to the habitat while spectators continued to watch the fish from the outside.

But this was far different, far worse. _He_ was the spectacle. He was the specimen in what was, essentially, an enormous test tube.

Grief, regret, despair. All of it still wracked his body in a crushing tsunami.

But still, _somehow,_ he straightened, floating up so he could be level with his captor. Terrified as he was, he had to remember what he'd told his brothers. He had to remember why he was doing this.

So none of the merpeople would ever have to go through it again.

He couldn't even ask about Zoro, didn't want him in the man's thoughts at all, only hoped desperately that the merman had saved himself. It was all he _could_ do. He'd promised Zoro everything was going to be alright, and it _had_ to be.

He didn't know what he would do if it wasn't.

He glared at Sakazuki with immense hatred, letting that fury overtake the sorrow, if only to keep himself from breaking down into the sobs he felt ready to submit to. He would not show this man weakness.

"Relax, Mr. Red," said Sakazuki, voice still muffled, but audible. "You'll be moved to more comfortable quarters. I only wanted to make sure I had your utmost attention for our initial chat."

"You have a shitty idea about how to get my attention," Sanji bit out, glad for his sharp teeth when he automatically bared them.

There was a long moment of silence, Sakazuki's eyes drifting over him uncomfortably, but Sanji forced himself to stay put.

Let the man stare. Let him stare at the one who would finally stop him.

When Sakazuki finally spoke, his voice was quiet, back to that calm tone that Sanji was beginning to despise. He wasn't sure why the man bothered with it when there was clearly a monster lurking beneath.

"Your mother and I had more in common than you think, Mr. Red," he said, Sanji instantly bristling, unsure why this was the man's chosen conversation starter. "We both loved and lost, far too soon."

"What she lost, she lost because of you," Sanji spit back, fists trembling at his sides as he swam closer to the glass. "She lost her own life because of you-"

"And the ocean, that which gave you and all of your kind life, stole from _me_ ," Sakazuki interrupted, placid demeanor shattered by the inhuman snarl that came to his lips. "All that I do here is so that I may live to see the day when the ocean will never take another human life."

Sanji said nothing.

His reasons meant nothing. No matter how much the man tried to justify himself, there were no more excuses as far as Sanji was concerned. This glass prison that surrounded him was proof enough of that.

Sakazuki glared at him for another moment before the anger began to fall from his face once more as his expression settled into something more passive.

But Sanji could see the way his jaw twitched, teeth grinding in subtle frustration, as if wishing for a cigar to clamp down on, to shroud him in that shield of smoke again.

The man closed his eyes briefly before meeting Sanji's once more.

"I'm not an unreasonable man," he said. "I do have my own moral compass. And I tried to negotiate, all those years ago."

Sanji's eyes narrowed as the man stepped forward, close enough that, even through the glass, the blond could see every hard line etched into his face, worn creases that tugged down on eyes and lips, dug there by frowns, not smiles. Gray stood out at his temples, as if years of unhappiness had clawed fingers over his face before combing back through his hair.

"I would have raised you as my son, Mr. Red," Sakazuki murmured, and it was a new tone, one that was weary, almost dejected, though his words only brewed burgeoning horror and disgust in Sanji's stomach. "You were my second chance. I would have shown you the utmost care and devotion that every child deserves. I would have kept you safe. I would have left your kind alone. But your mother made her decision. And lost far more than she would have otherwise."

A shiver ran its way down the length of Sanji's spine, sudden images flashing through his mind of himself growing up in a very different place, perhaps growing into an entirely different person.

Had his mother really faced this choice? Had it nearly happened by force…?

"Why the hell would she leave me with you after what you did to my father," Sanji growled in response, his mind spinning with rage that surely wasn't merely his own.

"Your father was not as heroic as you may have been led to believe," Sakazuki insisted, the lines in his face darkening as his brows furrowed, as dark as the trench which nestled Noah. "It was thanks to him that we learned the location of your colony. And in fact, the bracelet we had in our custody was gifted to us by him. He hoped I would take you. Humans have no place in the sea-"

"That's a lie!" Sanji shot back, yet another growl leaving his throat to grate through his voice, this one far more animalistic.

"Believe what you wish," Sakazuki replied with a slow tilt of his head. "But it seems that cowardice was a common theme in your upbringing. And it was cowardice that left you an orphan-"

It didn't matter. Sanji had heard enough. He wouldn't believe him. He wouldn't believe anything this man said to him. Whether it was true or not, he would not accept it from this man's mouth - this _murderer's_ mouth.

"Shut up! I _have_ a father!" Sanji shouted, surging forward to slam his fists into the glass, a flurry of bubbles like an icy blizzard spiraling from the impact. "His name is Zeff Red! He is who my mother chose for me! And he is who I choose now! And he would not stand for this! Even in the name of a better world!"

He wouldn't. He _knew_ his old man. He _knew_ who had raised him. He knew why he was who he was - who had shaped him.

And he knew why he was alive, and _that_ was because of his birth parents. No matter what had happened, he owed his life to them, plain and simple, and he could not remain quiet as this man stood there and tarnished that fact.

"I'm sorry for whatever loss you've suffered," Sanji hissed, continuing when it seemed he'd actually stunned the man into silence, if only temporarily. "Because look what it led to. Look what you've become."

He ran a judgmental gaze up and down the man's form, no longer a specimen himself, because it was clear Sakazuki knew nothing. He could observe, speculate, assume all he wanted.

But for all the research he could have done, he was wrong. He was wrong about everything, and it was Sanji who saw clearly.

Sanji knew what this man was. And Sanji understood which one of them still possessed his humanity.

"My loss," the blond eventually said, letting in a rush of water through his gills to clear his head. "My family's loss—no matter what mistakes we've all made in the past—it's made us stronger. And if memory is all we have, then that's something I'm willing to fight for. A better world does not have to come from any further sacrifice or bloodshed. Are you making those you've lost proud?"

It seemed he'd struck a chord when Sakazuki's lip immediately curled up, a tremor running through his broad frame, eyes flashing with raw anguish, long buried.

"Your father will not come," Sakazuki insisted, voice rising. "Your _chosen_ father has not once protested my methods. He has lied to you for all these years! And I have seen the hatred for you those brothers of yours hold! There is no-!"

"You can try to prove to me and yourself that a family is not worth having," Sanji cut in. "But through the good and the bad, I refuse to believe that. I will not let go of what has been lost. I will not change. I _will_ protect them!"

His fists hit the glass again, little more than those few inches to separate their faces now. Sanji's heart pounded in his ears, blood rushing furiously, and he let those instincts within him breach the surface, the aggression and dominance he'd felt the very first time he'd transformed.

He let it take over, a silent warning that the instant he was free, there would be absolute hell to pay.

Suddenly, Sakazuki's head turned, and Sanji's ears pricked when he heard another muffled voice, farther away, its owner invisible in the dark room beyond.

Still, the voice's warning was discernible.

"Sir! There's a Navy ship visible in the east!"

A second frantic voice, and Sanji thought he could make out a lit doorway, a small rectangle of light in the distance, framing two wavy silhouettes.

"Another was spotted comin' from the west!"

Sakazuki's fist slammed hard into the glass directly in front of Sanji's face, the water at the top of the tank giving a hard slosh, rattled by the impact. Sanji could practically see the simmering heat that seemed to emanate from that furious fist. If only it would melt through the glass, Sanji could be freed.

"Station guards at the labs. _Now_ ," Sakazuki barked, and those spidery silhouettes hurried off, followed by a slam which swallowed up the outside light.

The man's head whipped back to Sanji with a vengeance.

"No one will take what I have labored for, Mr. Red. Certainly not you and your righteous words."

One last disdainful flick of his eyes and Sakazuki too stormed away, the saturated red of his shirt fading into the surrounding darkness.

Sanji didn't move for a long minute. Even when it appeared the man had left, Sanji wasn't certain of his solitude, couldn't be, not when all that was visible now was the same blue glow he'd awoken to.

If he let his guard down again, there was no telling what would happen.

Yet, still, he felt himself sinking once more, tail curling on the bottom of the tank, forehead against the glass, where he closed his eyes.

He would see his father again. He would see his friends again. He _wasn't_ alone. Someone would come for him, surely.

Somehow it was Zoro's voice telling him that, a figment of comfort in his mind that he knew he couldn't trust so readily.

But he clung to it; he clung to the image of Zoro's face, his stupid smirk that had instilled him with so much confidence before.

" _You're okay, Zoro. I know you are,"_ he found himself murmuring before he was fully aware of it, because he refused to believe someone as strong as him could vanish from this world so easily.

" _Come for me. Get me the fuck out of here."_

* * *

"Steer clear of the Navy ships, got it, kid? Bring 'er in to the secondary docks."

"A-Aye, sir!"

The sounds of the boat's small crew preparing were behind her, but Kuina didn't move from her position at the bow, leaning over the railing as the wind whipped through her bangs, trying and failing to pull strands from the short ponytail she now wore to match the clumsy woman's.

The ocean spray sprinkled her with every dip of the boat over the waves, misting her borrowed shirt, a gaudy pastel button-down, and the wetsuit shorts she'd stolen before breaking out of the place that was now within view once more.

Perhaps it should have been a sight to behold, certainly one she'd never laid eyes on before, seeing Marineford Island come into view in the distance, the cloudless sky, the bright turquoise of the ocean, even the two large ships which loomed ahead, both heading for the island as well. The smoking man had said they were here to help, but it worried her all the same.

She couldn't appreciate the breeze that stole her breath, nor the seagulls that seemed to race their boat from above because she knew what awaited, and it was all she could do to keep calm, set on the mission ahead.

A gloved hand grabbed her arm suddenly, and she very nearly panicked, whirling around with the sword she gripped tightly, but Smoker merely dragged her back from the railing a few steps, steering her towards the boat's cabins.

"I want you out of sight," Smoker grumbled pointedly, jerking his head for her to follow him.

Reluctantly, she did, not without a subtle growl that came from the surprise, her free hand coming up to rub her arm, despite having received no harm.

She was practiced with walking as a human, not for reasons she cared to reminisce upon, even in the cumbersome sandals she now wore strapped around her feet, but it still took a little extra concentration to cross the deck, which bobbed and swayed with the boat's quick pace.

Still, Kuina entered the small bridge to join the others, stopping in the doorframe warily, seeing the pink-haired boy at the helm with the surly-looking blond beside him.

The woman, the one she'd impersonated, stood near the radar screen with apprehension on her face, an expression Kuina would never allow these humans to see on her own. They were hardly the same, after all.

This had been her own idea. She needed allies if she had any hope of saving Zoro and Prince Sanji. She needed these humans, whom she'd judged to be rebellious against Sakazuki's orders. She didn't like it, but she needed them. So tolerate the situation she would.

"Tashigi and I will survey the situation," the captain said to the group, and Kuina noticed that he actively stubbed out his cigars in an ashtray attached to the windowsill before turning to address her individually.

"You stay with those two while they secure the boat," Smoker continued, indicating the two young interns. "Once the docks are clear, the three of you follow. Radar shows Sakazuki already docked. But we take this slow if we wanna get your friends out.

Navy's on the way and the second any of us raise suspicions, all hell's gonna break loose. I don't know how Whitebeard got involved, but he won't be afraid to start something. So we approach with caution. Is that clear?"

"Crystal," Kuina replied, expression serious, meeting the captain's eye without fear, even if her heart hammered a rapid flutter in her chest.

And that flutter jolted when slender fingers hesitantly reached out to touch the blade of her sword.

"Can you really use this-?" Tashigi started to ask, but Kuina quickly yanked the weapon away with a warning growl.

"Want a demonstration?" she snapped possessively. "'Cause things'll be way easier with one less doppelgänger, don't you think?"

Tashigi jumped in alarm, the woman's eyes going wide behind her glasses, but they managed to narrow a second later, her brows furrowing.

"Are you threatening me?" Tashigi shot back irritably. "You caught me off-guard once, but you won't again!"

"You sure about that? It really wasn't hard, and I'm not even hum-"

"H-Heyyy, we're all on the same team here, right?"

A third voice entered the fray, the shorter of the two interns stepping up between the women with peaceful hands raised to frame his pink hair.

"I'm just glad we get to follow the girl with the sword…" Helmeppo muttered under his breath, unhelpful as ever.

Kuina huffed out a breath, something that felt oddly natural to express her irritation. Still, though she'd never admit it aloud, she knew why this tense aggression was assaulting her. Deep down, it was worry and fear, things she was determined not to succumb to, not now when lives were on the line.

"I'm sorry," she grumbled, averting eyes to stare hard at the wall.

Unfortunately, all she saw was her own reflection glaring back at her in the metal of a cabinet door, her face full of far too much vulnerability and uncertainty for her liking.

"I just cannot let them do this again," Kuina eventually admitted, self-conscious of the shrinking tone of her voice. "I can't let humans-"

A touch to her wrist, and though it was gentle, her first instinct was to pull away quickly. But the fingers were persistent, circling her wrist until she was forced to turn her head to see Tashigi's gaze.

What she found surprised her.

What she found was her own reflection again, and though she'd seen her own feelings in Reiju, this was very different. She saw everything, her own face, just the same as the real image in those cabinet doors.

" _Those_ humans," Tashigi corrected quietly. "You're not the only one who can't stand what they've done."

Kuina stared for a long moment, breaths steady but shallow. Because she saw the exact same uncertainty, the exact same fear….and the exact same determination to change things. All of it in Tashigi's eyes. In a _human's_ eyes.

A human. And here she stood on two legs just the same, though she was still herself. She still felt like herself, even with this different body, and maybe that was something to consider. Perhaps humans came as varied as merfolk…

" _Those_ humans," Kuina amended finally, meeting Tashigi's eye grudgingly.

She'd nearly forgotten they had an audience by the time she heard a subtle grunt of approval from Smoker, who nodded when she glanced over at the man, his arms crossed over his chest.

"Stay in the cabin," was all he said to her, then to the rest, "Lay low."

And without further meditation, he strode from the room to the deck, gesturing for Tashigi to join him.

Kuina said nothing more, alone in the small space with the two interns, Coby offering her a small smile before turning back to the helm to focus on their approach.

She chose to do so as well, narrowing eyes at the island that loomed larger with every passing second.

* * *

Their boat was thankfully inconspicuous, clearly a M.A.R.I.N.E.S. ship, easily unnoticed, particularly with the M.A.R.I.N.E.S. crewmen, out on the pier, preoccupied with the approach of not one, but two larger Navy vessels.

So Coby snuck them in from the island's southern side up to a smaller dock, close to the large building's entrance, making it rather easy for Smoker and Tashigi to hop out and secure the ship, the area devoid of potential hindrances.

Still, Kuina stayed crouched in the bridge near Coby's feet, hidden from view as per Smoker's order, gripping the hilt of her sword hard to keep herself grounded, even as Coby wrung hands anxiously on the ship's wheel and Helmeppo grumbled and paced.

She couldn't let their nerves affect her, not when it seemed fortune was on their side thus far.

So she'd afforded a glance outside, straightening just enough to peer out the window at the docks beyond, their immediate area free of people.

A glance to the end of the pier, however, showed a flurry of activity as Sakazuki's crew members, henchmen as she preferred to call them, scurried about in frantically confused preparation for the Navy's arrival.

"I'm sorry for all this."

Kuina tore her gaze from the action on the pier to look at the pink-haired boy, who, when she really looked at him, seemed hardly old enough to be out of the humans' high school, let alone piloting a boat.

But his expression was tired, and his pained tone had drawn even the wandering attention of Helmeppo, who stopped near the doorway to look over as well.

"You shouldn't have had to go through what you did," Coby murmured. "And I'm sorry we didn't do anything to help you sooner."

Kuina blinked, admittedly surprised by the apology, and she found herself lost for words, the room falling into heavy silence for a minute.

Until a long-suffering sigh left Helmeppo, who crossed his arms over his chest unhappily.

"Yeah…." the taller man added, his voice somehow managing to sound sincere, even through his sulky tone. "But in our defense, we're just interns. We had no idea what was _really_ going on-"

"Helmeppo," Coby scolded.

"Alright, alright," he huffed. "I suppose we still should have _investigated_ or something…. Honestly, screw this internship anyway. Sakazuki wouldn't even give us college credit! Join the summer program, they said!"

"It'll be fun, they said," Coby muttered automatically, only to receive an eye roll from Helmeppo, so another apology quickly followed. "Sorry. Dead meme."

 _"Long_ dead."

"You started it though."

Kuina was just beginning to feel a hint of an inadvertent smile tug up the corners of her lips as soon as the bickering started up, when, suddenly, closer voices outside, and she looked up to locate several men above on the landing in front of the building's entrance.

She ducked down a tiny bit instinctively, but it seemed they were hardly focused on the docks below.

Their movement was half obscured by the slots in the walkway's railing. But, after a few moments of staring, Kuina saw they were just beginning to lift what was clearly a large transport stretcher for sea animals, its sides concealing whatever they carried as they hoisted the poles up to their shoulders with some effort. Their cargo was clearly heavy.

She should have looked away, should have stayed focused on the plan, but she _couldn't_ tear her gaze away because it was too strange.

Why were they up there, with no tanks in sight? The landing merely wrapped around the circular building and climbed to higher tiers on either side.

Why were they maneuvering the creature _towards_ the doors, towards the front entrance, when she knew they had a manmade cove just around the island's curve that they used for bringing in big species to the rear tanks?

Why was there a glimpse of a deep green tail, too green to be any normal fish's col-?

Kuina's heart stopped in her chest, her mouth going dry and the breath shuddering out of her as forcefully as if she'd just transformed.

There was only one tail in the world that she knew was that shade of green.

" _Zoro_ ," she breathed with horror, and then she was up, shoving past Helmeppo, to the man's complete disdain, and running out onto the deck.

She didn't care if she was blowing the plan. She didn't care about Smoker's angry shout from the stern of the ship, didn't care for anything but the sight of that limp tail above and her own concentration as she sprinted across the deck, practically leaping the distance of the gangplank to the dock beyond.

She had experience running as a human. She had far more experience than she ever wished to relive, thanks to Sakazuki's loathsome "tests," but she could admit it was helping her now as she sprinted the length of the dock, the waving vegetation at the base of the building practically cheering her on.

Her eyes stayed fixed on the landing above, enough that she nearly crashed into the stairs' metal railing when she reached the bottom, though she quickly swung around it and started pounding up the steps, breaths huffing hard and fast.

"Tashigi?" one of the men blurted out in confusion when Kuina finally appeared at the top of the stairs.

And without thinking, she drew back her sword and swung the blade swiftly across the same man's throat with a fierce cry.

She felt the blade sink into soft skin, a strangled sound and a burst of red blood all she saw before her victim fell to the ground at his comrades' feet, twitching in his dying moments.

The other three barely had time to react before Kuina had them at blade-point, her teeth bared in ferocious rage.

"Drop him," she growled, in a voice that blurred the line between human and animal, and it got her what she wanted, the three men letting go of the stretcher poles, the carrier slumping to the floor along with its cargo.

And sure enough, nestled there in the heavy blue fabric that was a pathetic imitation of where he truly belonged, was Zoro, unconscious, and entirely, terrifyingly still.

A pang of cold panic shot through her as her eyes flicked over him, but she kept it off her face, even if her heart felt ready to explode from her chest.

Shuddering noises of shock from one of the men, the realization of what had happened to the unlucky victim crumpled at her feet finally sinking in, so she jerked her head to the side.

"Back off," she hissed next, though she didn't allow herself to feel triumph yet, not even when the remaining men slowly got to their feet. Because she saw the flick of eyes to her wrist, her bracelet.

And she was right not to let her guard down, because that instant was followed by a gleam in the sunlight, the barrel of a pistol….and a gunshot into the air when that pistol misfired, the blade of her sword doing the misdirecting when it sliced into the man's wrist forcefully, carving a red bracelet of her own design.

She had little time to revel in his scream of pain before she was moving again, across the landing to draw her next attacker away from Zoro, the bold fool running at her with bare fists alone, clearly set on tackling her, if his aim at her waist was any prediction.

What he got was a swift knee to the groin, a slam of the sword's hilt on the back of his head, and the sharp end of the blade nestling in his side when he tumbled to the ground, Kuina giving a vengeful twist of the sword to ensure the damage landed.

She pulled back, the sword practically singing in her hand, her palm tingling with the powerful energy still vibrating from the blood-soaked blade.

She wasn't scared, couldn't be, not when it felt so natural to wield, as if the weapon was an extension of her very arm, as fluid as water itself.

One man was running, Kuina noticed with a predatory eye, scrambling to escape near the top of the stairs, so she helped him with a quick charge and a push, sending him tumbling over the railing clumsily.

Somehow, he managed to hold on with desperate fingers for a few moments, but Kuina remedied that with a stomp of her foot, and then he was out of her way for good with a shrill cry.

That left one, who she was definitely still aware of when she heard the cocking of that gun, the stubborn man shakily lifting the weapon with his good arm, the other dripping blood that soaked dark pools on the metal beneath.

But instead of aiming at Kuina, a sinister grin twisted the man's features as he turned the gun on Zoro's prone figure at close range, with the intention to finish the job.

Her instincts snapped like lightning, her body darting forward, leaving her mind behind.

She lashed out with the sword, struck low and hard until the blade sunk into her attacker's stomach with a pained howl from the man before his finger could even pull the trigger, the gun clattering to the floor uselessly.

With a forceful cry, she again twisted the blade viciously, and with all her might, she whirled herself around, the sword still impaling her victim. She swung him to the edge of the landing, where she pushed forward again, driving the blade further into his torso.

And then, a great shove, fueled by nothing but inhuman rage, that lifted the screaming man up and over the rail, off the landing where he fell the great distance to one of the boats bobbing below. His voice was silenced when his body clipped the edge of the bow, smearing red over the white surface, and he slumped there, lifeless.

Kuina stopped, panting, slowly lowering the sword to her side amongst the carnage she'd wrought, limbs trembling. There were shouts from below, though their owners were unclear, but she was hardly aware because now all that was left was Zoro.

She whipped her head towards him.

Predictably, he lay there, just as silent and still, prone and pale, his lips tinged dark with a deathly shade of purple that had a fearful whimper escape her.

But she ran to his side, falling to her knees, the sword clanging to the floor with a metallic ring as she dropped it.

Her hands flew to his face, his skin cold, despite the heat of the sun, and dry, his bottom lip cracked with a hint of blood.

"Zoro," she hissed, shaking him, then louder, more insistently when she received no reaction. " _Zoro!"_

Nothing, not even a twitch.

How long? How long had he been out here?

She was terrified of the answer, but still, she had to act. There was _no_ time. She _wasn't_ too late, couldn't be, but there was still _no time._

So she moved, grabbing the poles to the stretcher and dragging Zoro's heavy form with all her might towards the stairs.

" _Fuck_ ," she grunted, struggling to maneuver her legs in a crouched position, but she forced herself to keep her balance, kicking away the fallen bodies of her attackers because she _needed_ a straight shot to the stairs.

And yet, it was the stairs. It was the stairs she couldn't do, she realized with helpless dread, eyeing the long distance to the bottom.

There was no way she could control herself going down, not dragging Zoro, not without hurting the both of them, or wasting more time with a slow descent.

Fuck.

She dropped the stretcher poles at the top of the stairs, already standing a few steps down, and she afforded herself three seconds to make a decision.

A decision that was stupid, but was the only option she saw in that moment.

Three seconds.

Zoro lay there, still as death.

Two.

She wouldn't let him go.

One.

Even if it cost her life.

So she fell to her knees once more on the top step, reached up and removed her bracelet without further meditation.

She wrenched up Zoro's arm and snapped it onto his wrist, just as she felt the tingles of her own transformation beginning.

Her eyes were on him the entire time, even when her legs fell out from under her as they snapped straight.

She hit the steps hard and started to slide, feeling the familiar hot scaling of her own tail rapidly appearing.

Her eyes were on Zoro, growing more frantic the longer he didn't move, the longer he didn't transform. She refused to acknowledge why.

So she clutched his arm for as long as possible, but she couldn't hold herself up, now fully-formed tail giving an uncontrolled buck, breath leaving her lips in one quick huff before the burning of her gills was back full force and she was falling, sliding roughly down those stairs.

She caught the edge of a step with a painful crack of her arm, started to roll, picking up speed as she tumbled with bruising force.

And then her head smacked the floor bluntly, just before she finally crashed to a halt on the pier below.

In her last moment of awareness, she thought she heard a slow gasping breath from above.

She slipped easily into the darkness.

 _ **TBC…**_


End file.
